The England winger came on in the second half and set up City's goal in the 2-1 reverse, a result that prevented them going top of the Premier League table. And Johnson says the sooner they get that game out of their system the better.
"We need to bounce back from a bad result," Johnson told the club's official website.
"I think Everton only had two shots at goal, but there were mistakes on our part.
"Even so, another day we'd probably have scored four. It was one of those nights. We have to put it behind us now and remember that there are still plenty of games to be played.
"If we get the three wins we want then everyone will forget about the Everton result, and we'll be there or thereabouts at the top of the table going into the New Year.
"One result doesn't make it all change."
City take on Newcastle United on Boxing Day, and then face Aston Villa two days later and Blackpool on New Year's Day.
Sunday will be a return to his native north-east for Johnson, who City signed from Middlesbrough, and he added: "It's always great to get back up there. I played for Newcastle as a kid so I followed them as well, and I was ball boy a few times.
"It's my favourite place to play, I'm excited, but they are making it difficult for teams.
"I always thought they'd stay up comfortably, they're getting back to what they were."