The stories are spilling out from Room 1213 at Marjory Stoneman Douglas High School so that the world knows just what it’s like to survive a mass shooting.

The Advanced Placement psychology class was in the building where Nikolas Cruz wrought his worst carnage in a shooting that left 17 at the school dead on Feb. 14. Three people in that room were injured and one died.

The students who survived are trying to heal, sharing the details in tweets that have been retweeted and liked tens of thousands of times since they started Friday. Other students, in other rooms of the 1200 building, have also added their stories.

It started spontaneously among the students, explained Ivanna Paitan, 16.

“People don’t really understand what happened,” she said. “My friend Stephany said we should write our experiences down and start something.”

Paitan’s account recalls going for her phone “seeing my classmate, Carmen, on the floor with a pile of blood.”

Carmen Schentrup, 16, a National Merit Scholar semifinalist, was among those killed. Another friend, Maddy Wilford, was shot three times. She has since been discharged from the hospital.

“I couldn’t breathe, I couldn’t hold myself up, I couldn’t think that I was alive, making me check my pulse,” Paitan wrote.

Danielle Gilbert, whose tweets said she’s a 16-year-old junior in the Advanced Psychology class, recalled hearing gunshots for a few minutes before they hit the classroom.

The glass in the classroom door window, she wrote, “exploded and flew everywhere, the classroom filled with dust and debris and we began to hear screams and moans.”

She didn’t fully comprehend that the classroom had been hit, she wrote.

“Once I stopped hearing shots, I stood up to see why those students were making so much noise and what I saw at that moment will haunt me for the rest of my life. I saw my classmates, my friends, people I knew so well, laying on the floor, covered in blood completely lifeless.”

Paitan has since had a tattoo put on the back of her left shoulder. “Fly High,” it says, with the number “17” etched in a heart in the middle of the two words.

She said that writing it down helped “kind of.”

The hardest part of going on, day to day, said the National Honor Society member is “the people who can make a change are still waiting for more damage.”

She said she’s started visiting a psychologist weekly.

“How we are feeling, no one should ever feel in this world.”