(ABC NEWS) -- Two friends recounted the unexpected moment they both were bitten by a shark while vacationing in the Bahamas, as they recover from their injuries back home in the United States.

Rileigh Decker and Summer Layman had jumped off their friend's boat in Bimini Bay together on Friday and were swimming back when the attack occurred.

"We were swimming to the ladder, and I kind of felt something nudge my leg," Decker, 20, told "Good Morning America" from her hospital bed in Florida. "We kept swimming, and then I felt a tug on my leg. And I knew right then and there that I was bit."

Decker said she had no strength in her leg and couldn't get herself back on the boat, so her friend pulled her back up. Summer, who has a medical background, then guided their friend as he wrapped a towel around Decker's leg and a rope above her knee for a tourniquet until first responders could arrive, they said.

"It was very scary," an emotional Decker said. "The fear of like thinking, you know, you're gonna die in the moment."