"I looked around to see if anyone else heard it because it was real faint," he tells PEOPLE. When no one reacted, 20-year-old Fernell assumed he was just "hearing things."
Until 10 seconds later, when alarms filled the theater.
"The sirens began to go off from the exit sign, a white flashing light," he says. "That's when my heart sunk in my chest. [I thought], 'Okay, it was gunshots I heard.' "
On Thursday evening, a gunman, identified Friday morning as 59-year-old John Russell Houser, opened fire on theatergoers taking in a showing of Amy Schumer's comedy Trainwreck, killing two and injuring nine more.
The two deceased victims were identified as Mayci Breaux, 21, of Franklin, Louisiana, who died at the theater, and Jillian Johnson, 33, of Lafayette, who died at the hospital.
According to authorities, Houser attempted to escape with the fleeing movie theater patrons, but after he spotted police near the exit, he turned back around, moving against the crowd, and took his own life.
He could have seriously injured many more, if not for the heroic actions of two teachers. One threw herself in front of the other, saving her life. The second teacher was then able to pull the fire alarm, alerting authorities and moviegoers alike.
"Had she not done what she [did] … he could have come into our theater," says Fernell, who was in the theater across from the one where the shooting took place. "I could have been the one who was shot. Once you turn the corner in the theater I would have been the first person he saw because I was in a chair right there.
"That scared me."
A Theater in ChaosAfter the fire alarm was pulled, all hell broke loose. Some moviegoers ran for the exits, but once they got outside, Fernell says, police did a good job of corralling everyone.
It was while he was filing out that he spotted a woman "lying down on the curb with blood coming down her leg," he says. "She was shot."
But instead of leaving her behind, someone had picked her and carried her outside, Fernell says. He watched a cop treat her wound, tying up the leg injury as police officers in assault gear rushed by.
"After about 10 to 15 seconds of being inside the building, you hear a bunch of gunshots almost like as if there was a war or something going on in there," he says. There was a pause in the shooting, followed by a few more shots.
"Then we heard 'suspect down,' " says Fernell.
As he was leaving the parking lot, Fernell "overheard two officers saying that that the suspect had committed suicide," he says.
On Friday, police described Houser as a 59-year-old "drifter." He had a history of mental problems and was involuntarily committed in 2008, according to authorities.
While Fernell was left shaken by the experience, he says Lafayette is a strong community that will find a way to heal.
"Lafayette is gonna come together now especially after this," he says. "I don't know if you've seen it everywhere but there's a hashtag #prayforLafayette everywhere.
"I've never seen anything like this before in Lafayette, and now that this is all going on I think we're gonna all come together and help each other through this."
With additional reporting by EMILY ZAUZMER
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