The 22-year-old became the most expensive English defender in history when he completed a £47.5m move from Everton last August but has found himself in and out of manager Pep Guardiola's plans following some questionable performances on the pitch.
Stones is due to come up against his old club for the first time on Sunday when the Citizens travel to Goodison Park, and the youngster admits that he struggled to adjust after leaving the Toffees.
"Definitely, my performances dipped and I made a few silly mistakes that I've tried to correct now," he told Sky Sports News. "It's only natural that these things happen, playing so many games.
"It's new to me, playing three games a week some weeks and I've got to find a way to adapt myself. Everyone's disappointed when they don't feel like they play well or they make a mistake.
"I'm the first one to hold my hand up and try and rectify that in training or the next game."
On his return to Goodison, he added: "There's mixed emotions. I've got a lot of friends there, I played a lot of games for Everton and a lot of my family has got friends there, so it's a big occasion for them, as it is for me. It will be strange to go back, as I'm sure it is for everyone the first time they go back to face their previous club."
City go into the game fourth in the Premier League, seven points behind leaders Chelsea.