Tweel had hoped to play soccer for Prince Edward Island at the Games, but surgery in September to repair torn ligaments in his right ankle ended his chances. Instead, he threw himself into swimming, a sport he'd only participated in to keep up his fitness.
"With the soccer ending in September I thought, 'Well, might as well try to swim,'" said Tweel on Sunday. "They wanted more people, because we wanted to get a full team here at the Canada Games, so I said, 'I've been swimming most of my life, might as well focus on that now because it's good exercise.'"
Tweel did more than try. He steadily trained for months while his ankle healed, earning his way on to P.E.I.'s swim team and qualifying for the 50, 100 and 200-metre breaststroke races at the Games.
It wasn't easy for the 17-year-old from Charlottetown. Training for competitive swimming exhausted him mentally and physically.
"After my surgery, when I started to swim again for the Canada Games, I wasn't getting faster right away. I knew it was because of my ankle, but I was just getting frustrated anyway and I really wanted to make the team," said Tweel. "We had 13 guys qualify and they could take 12. It was really stressful to get the (standard) times and get as high as I could in the FINA rankings."
Tweel added: "When I started I was just off the crutches, so it was pretty painful. I did nothing but pull for the whole practice. I remember the first practice that year I couldn't even get out of bed. I was just dead."
He also tried to cut fast food out of his diet to help him increase his fitness, but struggled sticking to his new regime.
"I tried to. It wasn't necessary for us to do, but I tried," said Tweel. "That's all I can say. I didn't do very well, but I tried."
That effort didn't go unnoticed by P.E.I. swim team coach William Calhoun.
"He was pretty much one of those athletes for me that did exactly what I asked him to do, even if it was not something that he had traditionally been good at," said Calhoun. "He's been pretty much, in every single event this year, 100 per cent best times throughout the season since he got his leg back to where it needed to be."
Calhoun may have been impressed with Tweel's work ethic, but the swimmer still needed to beat out the competition in the pool to qualify for the Games. Although he was hitting personal bests almost every time he swam, there was no room for error until he'd guaranteed himself a spot at a meet in Saint John in May.
"That meet pushed him up over the lip," said Calhoun.
Tweel's performance in the water was impressive for an athlete considered one of P.E.I.'s best young soccer players.
"Nick was a very strong soccer player. I mean, obviously, being involved in our provincial program shows a high level of soccer," said Jonathan Vos, technical director for the P.E.I. Soccer Association. "He was also selected to Team Atlantic one year. He would've been one of four Islanders selected for that team which then goes to nationals to compete against Quebec, Ontario, B.C., and Alberta.
"That's quite a high standard to make. At that age group that's the highest you can go to besides the national team."
Tweel comes from an athletic family. His sister Madeline is sailing for P.E.I. at the Canada Summer Games, with his mother and all three of his siblings heavily involved in Charlottetown's Bluephins Aquatics Club.
Calhoun believes that without that connection Tweel would've given up on swimming. But his family kept him around the pool, swimming in meets when his soccer schedule allowed.
"I think after soccer stopped for me I couldn't focus in school a lot because I needed the exercise. I was too wired all the time," said Tweel, who missed out on the 2009 Games in the 50 breaststroke by just a few tenths of a second, despite never training seriously for the event.
"I know that I'd missed the time for Canada Games last time by a tiny, tiny bit, so I was like 'Might as well keep going.'"
After talking to his parents about shifting his focus to competitive swimming, Tweel went to Calhoun in October and told him he wanted to make the provincial swim team.
"We had a provincial swimming competition that he got selected for — it was a Canada Games pre-competition event in December — but because he injured himself, he wasn't able to go to that," said Calhoun. "But, he didn't want it to be deemed as, 'Well, I just don't want to go,' so he trained just as hard as everybody else, up to that point, and really started to shine with his training once everything calmed down with his leg.
"From January right up until yesterday he's been pretty much 100 per cent committed and worked really, really well within the training structure."
Still, Tweel has one more goal after the Games are done.
"I want to go back (to soccer)," said Tweel. "I kind of want to stay with swimming too. I don't want to be as far away as I used to be with it."
Added Tweel: "I did talk to my club coach a month ago and he wanted me as soon as Canada Games was done right to soccer. I said, 'Whoa whoa whoa, I need to slow down a little bit, maybe I'll come back, but I need to take it easy for the first little while.'"