Ryan O'Connor, 18, had a life-saving heart transplant last November but suffered problems with his circulation.
Following the complications, surgeons had no choice but to amputate both legs at the knee.
Despite everything he has been through, Ryan has a positive outlook on life and his future.
"I have nothing there that can be beat me yet," he told UTV.
"But it was like going through hell as it were, it was like going through hell and I just went through it and more or less smiled at death at the end of the day and got through everything and came back just as good as I was before, even better maybe."
Following a gruelling few months of treatment and therapy, Ryan has received new prosthetic limbs.
And he is taking on his newest challenge with characteristic positivity.
"Everything in my life now is a challenge, everything's thrown at me and I try to get through it and if I can't I'll try it again and I'll get through it in the end and I want to prove to everybody that I can do what nobody expects me to do," he said.
"It's one of them things that becomes hard but it gets easier and easier each time you go through it."
His mother Donna is amazed by her son's quick recuperation.
"It's not that we have forgotten about the hard times we've been through," she told UTV.
"It's we're amazed at how well Ryan has come on because he has been through so much, especially today he was discharged from his rehab which happened really quickly for me anyway. He's doing everything and more."
Last summer Ryan carried the Olympic Flame and it seems he has set himself an even bigger challenge for the future, as he wants to compete in the Paralympic Games.