Since this has happened, my belly button looks different, too. "Saggy" would be the best way to describe it, like there is too much loose skin inside the belly button, it's hard to describe.
Also, it seems prone to some sort of skin irritation / infection now, which makes it itchy and smell bad. I experimented with H2O2 which was neat because of the foaming action but I've actually had better results with a little hand sanitizer and a q-tip -- a good cleaning once a month or so seems to help.
I don't think it will really ever be back to normal. I just hope it doesn't get saggier with age.