By John Lauritsen

MINNEAPOLIS (WCCO)Federal investigators are now trying to piece together what tore apart a Twin Cities school Wednesday.

Co-workers and friends Ruth Berg and John Carlson died when a gas explosion flattened part of Minnehaha Academy’s Upper School.

Kristin Overton, the school’s guidance counselor, is counting her blessings Thursday night.

“My co-worker who works across the hall ran into our office and just yelled, ‘There’s a gas leak, get out of the building,” Overton said. “She didn’t even finish her sentence and the explosion happened.”

The blast knocked Overton to the floor. The window blew out and then the entire ceiling came raining down.

Seven-months pregnant with her first child, Overton quickly crawled under her desk.

kristin overton Minnehaha Academy Survivor: I Need To Get Myself & The Baby Out

Kristin Overton (credit: CBS)

“What really struck me was how loud it was. You could almost just sort of feel your entire body shake. It was pretty violent,” she said. “My first thought was, ‘I need to get myself and the baby out of here.’ It was definitely full of panic.”

Overton was immediately aware that what was left of the room was full of dust and debris, making it hard to get any air.

She, along with student Chimali Day and her parents, found a back door and got out.

Read More: Recovering Minnehaha President Mourns The Loss Of Explosion Victims

That is when she realized how dangerously close they had been to the explosion.

“I don’t even know if I can put it into words. I sort of felt gob smacked by it,” Overton said. “It was just striking to me the devastation and how quickly and how violently it happened.”

She was taken to a doctor who assured her that her baby boy was OK.

“I’m just thankful that I’m healthy and he’s healthy, and got to hear his heart beat,” Overton said. “That was a huge sigh of relief for my husband and I.”

minnehaha before and after Minnehaha Academy Survivor: I Need To Get Myself & The Baby Out

Minnehaha Academy before and after the explosion (credit: Google Earth/CBS)

A sigh of relief, but also sadness over the loss of two friends. Receptionist Ruth Berg and custodian John Carlson were killed in the blast.

Overton will look for the school community to hold each other up, better than any building ever could.

“We’ll miss them. It’s going to be different not having them there this fall, for sure,” Overton said.

She says the loud explosion left her with a headache most of the day.

She will go on maternity leave at the end of next month.

Her office was destroyed in the blast, so she is not sure what she will return for the school year.

A GoFundMe page has been set up to help rebuild the Upper School.

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