Hargreaves joined City on a one-year deal on Wednesday. The midfielder was available on a free transfer after having been released by Manchester United after struggling with injuries during his spell at Old Trafford.
The 30-year-old told City TV: “It’s difficult for people from the outside looking in. You would think ‘ there’s something gone wrong there, the guy’s made out of glass’.
“But anybody who knows me and knows the way I play, I take it very seriously and very professional.
“So obviously I don’t think everybody had all the facts and a lot of things (injuries) happened that basically I wish wouldn’t of and it’s just a huge learning curve for myself and I would have never have anticipated I would ever find myself in that position.
“So I’m just happy that that chapter is behind me and I’m looking forward to just playing football and having fun, having a good time, joining in with the lads and competing again.”
He added: “It was my life – I missed Champions League finals, I missed World Cups, I missed so many big games that I would have loved to have been a part of.
“Its difficult when you’re in it and you’re trying to find a solution to these things, you seem to be not going any further forward and it was incredibly frustrating.
“So I basically spent all summer just training, proving to myself that I can work hard, that I can train and sustain the load that is demanded of a professional football player.
“I hadn’t made my mind up this summer, I just wanted to train hard and then see how it felt and I didn’t use an agent.
“It just kind of (happened) – I think in life you can’t chase things, you’ve just got to let things happen and that’s what it was and, you know, I’m looking forward to the future.”