(CNN) -- Michael Dunn concedes it doesn't make sense he never called police after fatally shooting a teenager at a Jacksonville, Florida, gas station, but said Tuesday he wasn't in a rational state of mind -- not immediately after the killing, not hours later, not the next day when police questioned him.
"You're right. It sounds crazy. ... I can just tell you I didn't do it," Dunn testified. "It makes sense that I should have. We didn't. I can't tell you why."
He and girlfriend Rhonda Rouer were having an "out-of-body experience trying to process what was happening" following the shooting. After learning almost six hours later that he had killed 17-year-old Jordan Davis, he became "crazy with grief," vomiting and experiencing stomach problems for about four hours before taking a nap, he said.
Dunn, 47, took the stand on day eight of his trial on murder and attempted murder charges stemming from a November 2012 incident in which he opened fire on an SUV full of teenagers following an altercation over loud music.
He has pleaded not guilty to all charges, saying he fired in self-defense after Davis threatened him with a gun.
"My intent was to stop the attack, not necessarily end a life," he testified. "It just worked out that way."
Did Jordan have a shotgun?
On the stand, Dunn testified that -- after overhearing his life being threatened -- he saw "about four inches of a barrel" (of a gun, perhaps) and then another threat.
"I'm looking out the window and I said, 'You're not going to kill me you son of a ....," Dunn said. "And then I shot him."
Yet his fiance, Rouer, testified herself Tuesday that -- after she came out of a gas station -- Dunn didn't tell her that he had seen a gun. The prosecutor then pressed her with more questions: Did Dunn mention any weapon to her? A stick? A shotgun? A barrel? A lead pipe.
Each time, Rouer's answer was the same: No.
In fact, police and prosecutors have said the teens were unarmed.
Yet Dunn told the court that Rouer was mistaken and that he told her "at least one time."
Assistant State Attorney John Guy showed Dunn a letter he wrote to Rouer from jail 12 days after the shooting, in which he mentions that Rouer told prosecutors Dunn never told her he saw Jordan brandish a gun.
"He asked what I had told you, and I then realized that we hadn't really discussed what happened as we were more concerned with whether or not anyone was hurt," Dunn wrote in the December 5, 2012, letter. "Let me assure you ... there was a weapon."
Dunn was adamant during his testimony that he saw a gun, saying it repeatedly, and when Guy asked why he told police the day after the shooting that it might have been a stick, Dunn said he told police that only because he thought they were "competent" when they claimed the teens were not armed.
Defense attorney Cory Strolla has hammered police witnesses over their handling of the crime scene, saying they failed to properly search the bushes and Dumpsters for any weapons the teens may have ditched.
After firing three volleys of 10 bullets, prompting the teens to flee the gas station parking lot, Dunn and Rouer left, too. They weren't fleeing because Dunn felt he'd committed a crime, he testified, but because they needed to get to a bed-and-breakfast in St. Augustine so their 7-month-old French bulldog, Charlie, could "go potty."
"We might be in trouble with the local gangsters, but I didn't do anything wrong," Dunn said, explaining his thought process leading to his decision to leave the well-lit parking lot where numerous witnesses had seen the altercation and aftermath.
It began with 'thumping' bass
The couple was staying at the bed-and-breakfast because it was pet-friendly and close to Dunn's son's wedding in Jacksonville, he said. They stopped at the gas station after leaving the wedding because Rouer wanted some white wine and chips, Dunn said.
That's when he heard heavy bass "thumping" from a red Dodge Durango parked next to him. Rouer testified previously that Dunn told her he hated "that thug music," which Dunn contested during his testimony. He said he wouldn't have used such terminology -- he said he prefers the term "rap crap" -- though he has labeled his fellow inmates "thugs" in jailhouse letters.
Asked if the music made him angry, he said, it's "not my style, but when I was a kid, my parents didn't like rock 'n' roll." Asked if the music's volume upset him, he said, "My eardrum was vibrating. It wasn't loud; it was obnoxious."
Dunn painted himself as perfectly collected for most of the altercation, saying he was "not mad at all" with the teens and politely asked them to turn down their "ridiculously loud" music. He thanked them when they obliged, but then Davis grew irate, he said.
He heard a flurry of profanity -- "f*** him, f*** that" -- and while Dunn felt it was "mean-spirited," he didn't roll down his window, he said. He had "no reaction at all," he testified.
The music came back on, but not as loud, he said, but "I wasn't going to ask them for any more favors." He heard more angry words from Davis, who Dunn claimed called him a "cracker" loudly enough for Dunn to hear over the bass coming from the stereo.
He continued looking forward, hoping Rouer would return to the car, he said, but the situation escalated with Davis saying, "I should kill that motherf***er."
"I'm flabbergasted. I must not be hearing this right," he said, recalling how he turned toward the Durango and saw "two guys with menacing expressions" looking at him. He rolled down his window and asked calmly if the teens were talking about him, he said, explaining that he was not taunting the teens so much as ascertaining about whom they were speaking.
"I wanted to know if I was that m-f'er," he said, using an abbreviated version of the profanity he had spoken earlier. "I wanted to make it clear that I had said, 'Thank you.' I didn't mean any disrespect."
'You're not going to kill me ...'
He then saw Davis reach down and pick something up, which Davis slammed against the door, making a distinctive thump. He saw about "4 inches of a barrel" from a 12- or 20-gauge shotgun above the window, but Dunn didn't reach for his firearm, he testified.
Davis then answered his question, saying, "Yeah, I'm going to f***ing kill you," Dunn recalled, saying he was stunned and "in fear for my life," but his pistol remained holstered in the glove compartment.
Davis then told him, "You're dead, bitch," Dunn testified, and "I became even more fearful at that point. I thought I was going to be killed."
He remained composed, he said, hoping the situation would de-escalate. It "wasn't to the point where I was ready to use deadly force," he said.
That's when Davis' door opened, "and this young man gets out and as his head clears the door frame, he said, 'This s**t's going down now.' " Dunn said he immediately thought, "He's coming to kill me."
Dunn said aloud to himself, "You're not going to kill me, you son of a bitch," as he opened the glove compartment, grabbed his pistol, dropped the holster at his feet, chambered a round and began firing, he said.
"I pointed. I didn't aim. I didn't use the sight," he said.
Evidence and witnesses in the case indicate he initially fired three times, then four more before getting out of the car and firing three more times at the fleeing Durango. Three of those shots hit Davis -- one in each leg and one through his liver, lung and aorta.
Dunn said he wasn't sure how many times he fired. He had "tunnel vision" and his hearing dimmed, he said. He wasn't even fully aware that the Durango was pulling away, he said.
He got out of the car, he said, to make sure the teens couldn't fire blindly at the back of his head as they pulled away, or at Rouer as she exited the store. He wanted "to keep their heads down," he testified.
Rouer came outside, and he told her to get into the car. He then drove 40 miles south to their room in St. Augustine, thinking he'd simply "made them go away." Rouer was "hysterical" on the way there, he said.
'I know why you're calling'
Once at the hotel, Dunn took the dog outside for his walk before ordering a pizza for Rouer, whose "stomach was in knots," he said. He didn't have any appetite, Dunn said, and he poured himself and Rouer drinks, rum and colas, in hopes of calming their nerves.
"We were stunned and horrified, just couldn't believe things escalated the way they did over a common courtesy," Dunn said.
Dunn said he was anxious at the hotel, fearing the teens in the Durango might come looking for him, but Guy, the prosecutor, asked Dunn to explain why he parked in front of the hotel and left his gun in the glove compartment. Again, Dunn said he wasn't in a rational state of mind.
When Rouer saw the news report the next day about the shooting and Davis' death, she told Dunn to take her home to South Patrick Shores, about 130 miles south of St. Augustine.
"She was panicking and almost mute," he said. "She couldn't really talk other than to say, 'Take me home.' "
Concerned for Rouer's well-being, Dunn opted again to forgo calling the police. He wanted to get her home and talk to his neighbor, a law enforcement officer with the U.S. Department of Agriculture, in hopes that he could introduce him to his local sheriff, he said. However, Guy introduced phone records indicating that the neighbor called Dunn, not vice versa.
"Hopefully, they would listen to my side," Dunn said, adding that he had no idea he'd be charged with murder.
While Guy said Dunn's actions were those of a man who knew he had committed a crime and fled the scene, Strolla, the defense attorney, pointed out that Dunn is a pilot, yet he never tried to flee in his plane. Nor did he ditch his vehicle, or even hide it, and he never called any airline, bus or car rental company.
When a Jacksonville homicide detective contacted him after he arrived home, he told the detective, "I know why you're calling. It was self-defense," Dunn testified.
Closing arguments are expected to begin Wednesday. In addition to the count of first-degree murder for Davis' death, Dunn also faces three counts of attempted first-degree murder related to the other teens who were in the vehicle and survived.
If a jury finds Dunn guilty, he faces up to life in prison.