That's happened to me with a female character of mine. In the first storyarc, I kept having to look at previous pages to makes sure I had her hair rolled to a certain side. Then once I took a hiatus(unofficially) from the book, I started drawing her and overproportioning her(she's muscular, but I was really overdoing it in my sketchbook). Just with the last few years(since i started back on the series) I started drawing her "correctly" again.
I had another character that had a Chinese dragon tatt on his head(he's bald)- on the left side. When I started doing the series again, I started drawing it on the right side- I had to go and correct it.