The City boss confessed feeling "shame" after a confrontation with a TV crew member in the wake of the Citizens' 2-1 defeat at Newcastle on Saturday.
When the match concluded, an emotional Guardiola entered the St James’ Park pitch and had heated discussions with match official Sam Barrott and Newcastle’s Bruno Guimarães, while also handling the headphones of the camera operator.
"I said sorry," the manager remarked. "I feel embarrassed, ashamed, looking back. It's not acceptable. I immediately apologized to the cameraman. I am who I am. After 1,000 games I’m not a perfect person, I make huge mistakes."
"What is for sure, I defend any team and my club, without a doubt. The reason why I want to defend my team is no doubt – because from my experience to win the Premier League we have to do 100 points, high nineties, otherwise we don’t win it."
The team sits in third and are seven behind the Gunners after what was their fourth league defeat of the season. "Losing four games out of 12 we have to improve a lot," he conceded. "Mathematically, it’s possible still achieve all."
When questioned if this meant the quadruple could be achieved, he responded: "As a seasoned reporter, have you ever heard me discuss four trophies in December during our historic run? Never."
Regarding his confrontation with Guimarães, the coach explained: "We have known Bruno a long time and post-match, home or away, we converse. We often meet and I always have a good relationship. I enjoy it. I’m an emotional guy, I love to talk and move my hands."
Guardiola would not be concerned if an opposition manager addressed his squad right after the final whistle. "Not if it's respectful as I do, it's fine," he said, mentioning the referee. "The referee was involved throughout the match, constantly. Goodness, very much so."
City were unhappy that the officials did not award City a penalty for a Fabian Schär challenge on Phil Foden, and doubted Bruno's positioning when Harvey Barnes scored Newcastle’s 70th-minute winner. Subsequent images indicate the Brazilian was onside.
Guardiola will take charge of his 100th Champions League game against Bayer Leverkusen this week. "It’s quite good, it means that every season we have been there," he commented.
City have 10 points after four games of the league phase, and Leverkusen hold five.