The winger featured in victory over Real Mallorca on Sunday.
Reflecting on his debut, Tommy told the club's website: "I'm very happy and proud.
"So many things went through my head. I'm living a spectacular dream, and even more so to be able to make my debut at Camp Nou and for the club of my life.
"It's the dream of a kid who started playing here, enjoying himself, having fun and learning... I've been at the club for 11 years. It's a goal for everyone and it's spectacular. I'm happy and proud.
"I still can't believe it, it's hard to wrap my head around. We had an impromptu dinner with the family and I tried to rest, but I couldn't really get much rest, to be honest, because I had a match with my team the next day.
"Now I have to stay grounded, but be ambitious and keep working so that more days like this come."