(CNN)Every time Abdulrahman Al-Dahhan closes his eyes at night, he hears the screams of friends and family in Syria pleading for help.
The voice messages he's received chronicling their pain make it impossible to sleep, he says. Haunted by their cries, he lies awake tormented by guilt. He worries that each moment he rests, thousands back home in Syria are still buried alive under rubble.
More than 33,000 people have died across Turkey and Syria since a 7.8 magnitude earthquake struck the region on February 6. Nearly a week later, a lucky few are still being pulled alive from the rubble but hopes of finding additional survivors dwindle amid freezing temperatures.
"It's destroying me," Al-Dahhan, 31, told CNN. "When it happened, I was receiving constant voice messages, jumping from number to number on WhatsApp, each one is someone crying, telling me they are seeing people dying around them. I can't stop hearing them."
Al-Dahhan, a Syrian-American aid worker for Mercy-USA, a Michigan-based non-profit working in communities across the globe, has spent the past week traveling around the United States to raise money for earthquake relief. So far, he says he has raised $100,000 by fundraising at schools, places of worship and efforts on social media.
Meanwhile, on the ground, his colleagues who survived have been in a race against time, using the funds raised by workers like Al-Dahhan to help rescue those still trapped under the rubble and deliver relief to shell-shocked survivors.
Mercy USA's staff in Turkey are seen together. Nearly everyone in this photo is now homeless, according to Mercy USA's Abdulrahman Al-Dahhan, and three are trapped under rubble.
Since the earthquake, Al-Dahhan says he has not properly eaten and can't sleep for more than 10 minutes at a time, the exhaustion evident in his voice.
"At least I get a little bit of relief, knowing what I'm doing matters, because the more I can fundraise here, the more it helps out there," he said. "But I am in constant stress that I'm not doing enough and I need to keep going. When I sleep, I feel guilty. I need to be awake every second. I need to be working. I want to get more updates. I feel like I'm operating here, but my mind and soul are there."
He describes in detail the photos he's seen from the ground and recites story after story of the horrors that keep him up at night. One of them is about a colleague who crawled out of the rubble with his 5-month-old baby and returned to save his wife and daughters, desperately digging in the freezing rain for two days until they were rescued.
Another story is about a family that lost two sisters in the earthquake, leaving their children orphaned. When their brother learned of his sisters' deaths, Al-Dahhan says, he suffered a heart attack from the shock and died -- also leaving his children fatherless.
Al-Dahhan's voice cracks as he details each story, but he does not allow himself to cry.
There is no time to mourn.
Syrian Americans lead urgent relief efforts
Ameer Alsamman was on the phone with a friend in Latakia, Syria, when he heard screaming and loud shouts. Then the call dropped.
"My mind started racing and I immediately thought it was an Israeli airstrike, since we have had a few of those in Latakia over the past few years," Alsamman, 27, told CNN. "When I saw the reports of a massive earthquake in the middle of the night, I began to wish it had only been an airstrike."
He spent the next hours in agony, he said, watching images of death and devastation pour into his phone with no way of knowing if his friends or family were trapped under the rubble.
"I have never felt as helpless as I did that night. All I could do was watch on and hope that my loved ones would make it," he said.
It took three days after the quake for the first United Nations convoy to cross through the Bab al-Hawa crossing, which is the only humanitarian aid corridor between Turkey and Syria. Instead, volunteers, including the organization Syria Civil Defense, also known as the White Helmets, led rescue efforts to help Syrians trapped under the rubble.
"It felt like no one was there for them, no aid was coming through, the only organizations able to provide aid were the ones already there," Al-Dahhan said.
"It made the situation more frustrating."
As the clock ticked, the opportunity to rescue survivors decreased, igniting panicked efforts from Syrians in the US like Alsamman and Al-Dahhan to raise as much money as possible for organizations on the ground.
Doing nothing was not an option.
As Al-Dahhan travels to raise money in person, Alsamman is using social media, so far raising over $1,000 for reputable international organizations on the ground and 10 food boxes that were delivered directly to those affected.
Ameer Alsamman speaking at Lebanese American University.
Nour Al Ghraowi, who immigrated to New York City from Damascus, Syria, following the civil war in Syria that started in 2011, is also helping through her work as a communications coordinator with Karam Foundation.
The nonprofit, which Al Ghraowi says "seeks to empower Syrian refugee youth and families nationally and internationally through access to innovative education, community-driven aid and skill development," has raised more than $49,000 for earthquake relief.