The steps may seem slow, but doctors say his recovery has been remarkably quick. In less than a minute on June 17, Sebesta's life changed forever.
"The longest 15 seconds of my life," he said.
The 15-year-old was in waist-deep water at Surfside Beach with his church group when the outing took a turn for the worse.
"I just felt something clamp down on my leg," Sebesta said.
He doesn't know how, but he started fighting for his life with what was believed to be a black-tip shark that's about 6 to 8 feet long.
"In the back of my mind, 'I could die,' and, 'Who gets bit by a shark?'" Sebesta said.
He punched the shark's head, gouged the eyes and reached with his hands for the shark's mouth.
"I didn't really think I had it in me to fight like that," Sebesta said.
Now a fixator holds his left leg to heal nerve damage. He's still working on strength in his left hand.
"The strength in my fingers," he said. "But I'm determined to get back out there and do everything like I used to do again."
It's important for the left-handed high school athlete. Though he says he can golf right-handed, getting back to baseball or football will be a longer process.
He says faith, family and friends have pulled him through but he does wonder why that shark picked his leg.
"It's still yet to come to me why. I guess it was just God's plan. And God, he has something for me up ahead the road," Sebesta said.
Sebesta says he's always loved sharks, and even though he now dons scars from one, he still loves them and hopes to study them one day.
He expects to be in a boot and on crutches by his first day of his sophomore year at Needville High School.
Find Christine on Facebook at ABC13ChristineDobbyn or on Twitter at @christinedobbyn
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