City put Arsenal to the sword 3-0 at Wembley on Sunday, securing a first trophy under Guardiola's reign in dominant fashion.
De Bruyne has been the star of City's march towards the Premier League title, but it was old favourites Sergio Aguero, Vincent Kompany and David Silva who got the goals at Wembley.
"We deserved to win," he told Sky Sports. "I think we have had a good feeling all season but it's not finished yet, we know what we have to do in the league and Champions League.
"We have to maintain the same focus.
"I think the potential at this club is huge, with the squad we already have, it's an amazing job and we play like the best in the world, it's very exciting to play here."
Right-back Kyle Walker made a brilliant last-ditch challenge to prevent Pierre-Emerick Aubameyang scoring in the opening 10 minutes and putting a wholly different complexion on the game.
"It's been a long time coming, glad to get my first one," he said.
"It's very special. I was nervous, not won on [the] last two occasions [at Wembley with Tottenham]. Everyone wanted to win, we obviously needed to kill the game, Sergio took his goal great."