CNN  — 

If one of many small moments of Iliana Monteagudo’s last night in her Surfside, Florida, condo had gone differently, she said she believes she would not be alive today.

Her credit cards were already in her purse, she checked her balcony door, she couldn’t find the staircase at first: all details she and her son credit with saving her life.

Monteagudo is one of the survivors of a partial building collapse last week. Rescue teams are still searching through the debris, having recovered 18 people who were killed, in hopes of finding answers for the families of the 145 people still unaccounted for. And investigators are on the scene to try to discover what initiated the horror.

Monteagudo told CNN’s Chris Cuomo that the evening before the collapse, she put her pills and her credit cards in her purse and lit the candle for the Lady Guadalupe, considered a national symbol and matriarch for Mexicans and Mexican-Americans, as well as an important Catholic figure.

She went to bed, but around 1:00 a.m. she was woken by what she called a “rare force.”

Believing the feeling came from an open balcony door, she went to her living room to try to close it. But then behind her she saw a crack coming from the ceiling, quickly snaking down the wall and opening fast.

“Something inside of me said run,” Monteagudo said. “You have to run to save your life.”

In moments, she put on the first clothes she could find, grabbed her phone and her purse, blew out the candle and ran out of her apartment, she said.

Once in the hallway, she found quiet: no panic, no alarms and no one else running.

She knew not to take the elevator but didn’t know that the emergency stairs were just beside her unit, so she went to the farthest set of stairs instead.

“If I knew that, maybe I would have taken that one,” Monteagudo said.

But as she was flying down the six floors of stairs, pleading with God to let her see her sons and grandsons again, she heard the sound of the tower she lived in collapsing. If she had been in the stairs closest to her home, she likely would have been crushed, her son said.

“She had to wake up early the next day, the next morning,” her son Andres Alvarez said. “She didn’t take her sleeping pill because she was afraid she was going to oversleep. If it wasn’t for that open door… if it wasn’t for that wind… if she hadn’t seen that crack… she wouldn’t be here telling the story.”

Now, she is safe, Monteagudo said, but she cries for her neighbors, lost in the building she moved into six months ago. Her move came after 40 years living in Miami, telling her friends one day she would be living in Champlain Towers South.