Photo: Jordan Vonderhaar/Getty

When gunfire rang outat Robb Elementary Schoolin Uvalde, Texas, on Tuesday, third grader Adalynn Garza took shelter in a classroom and practiced what she was taught.
“I just sat down and stayed at a level zero,” Adalynn tells PEOPLE. “That means no talking and stay quiet.”
“People kept saying that it was fireworks,” Adalynn recalls, but as she heard loud pops coming from the fourth grade building, she feared something worse was happening. “I said, ‘No, it was a gun’ … because a firework does not sound like that.”
Memorial for the 21 victims of the Uvalde school shooting.Elaine Aradillas

“I couldn’t sleep last night,” Adalynn says. “Because when I was sleeping it just came through my head.”
The shooter is believed to have crashed his car in a ditch near the school and then barricaded himself in a building on campus — Adalynn notes that every classroom door stays locked from the outside, so it’s strange that he was able to enter in the first place.
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Dr. Daniel Guzman of the Cook Children’s Health Care Systemtells PEOPLE, “Unfortunately, to say that we can do one step and our kids will get over this and we’ll all be over this [is false]. This has long-lasting effects on all of us.”
“Letting the children know that we’re there for them –– that despite this horrific incident that occurred, that we are here to help them get through this and that they’re safe,” Guzman continues. “It doesn’t feel that way right now obviously.”
“It’s going to take months, if not years, for these families to heal,” Guzman addss. “The healing takes time.”
In the meantime, “I feel scared,” Adalynn says. “Because what happens when it happens again?”
source: people.com