Victory against Arsenal means Guardiola becomes the first manager to win five League Cups in England.
He said afterwards: "What can I say? When you win a trophy is important. It was special because we had a tough two weeks. What they did in the Champions League is so difficult. In the first 15 minutes they suffocated us, we could not breathe. After that we won some second balls and started to play.
"I'm really pleased because Mikel (Arteta) created a team that is almost unbeatable. A fifth Carabao Cup in 10 years is not bad. Every time you win a title it looks more difficult than in the past. it is really difficult for many reasons.
"When you start to win and the generation is young you can continue that. I need to know them. I need to know how they behave in certain moments. Today in modern football everyone is so competitive and difficult. I think we learn for the future and hopefully next season we can do better.
"We are still not the team like Arsenal are or like we were in the past. We always found a way to win titles."
On the Premier League title race, Guardiola added: "I would love to be nine points in front to be honest. It's in their (Arsenal) hands. We need time, an incredible break. I am exhausted and after we see step by step."
Asked about two-goal Nico O'Reilly, he added: "Maybe he was the signing of the season. When we started the season we had a long conversation with him. He started to play at left-back and impressed a lot.
"He can play in many roles, he is a guy in the final third in a position he likes. He made two fantastic goals."