Guardiola's side wasted their chance to reach the final as poor finishing and sloppy defending allowed Arsenal to come from behind and snatch a 2-1 victory in extra-time on Sunday.
With City trailing 11 points behind Premier League leaders Chelsea, their last realistic chance of silverware vanished at Wembley, leaving Guardiola to face the uncomfortable reality that he has failed to provide the trophies expected from him when he arrived last year.
Having dominated in the Spanish and German leagues with Barcelona and then Bayern Munich, while also winning two Champions League titles, Guardiola has found life much harder in the cut-throat world of the Premier League.
The Spaniard admits this season has been a learning process and, with his ego clearly bruised, Guardiola promised City would be much improved next term once he has time to make changes to an underachieving squad.
"We will improve next season. We will be strong, especially in the games away against the Premier League teams," he said.
"For what I have done in my past the pressure will be on my shoulders for the rest of my career.
"Always in my life and always in the rest of my life I try to be better. That is all.
"Some players will stay and some will come in. I will try to be proactive.
"That is what I want to do. I'm not a guy who complains."
After leading City to 10 successive wins at the start of the season, City have gradually fallen back into the bad habits that prompted the club's Abu Dhabi-based owners to axe Manuel Pellegrini and bring in Guardiola.
