21 again?

I recently turned 35 - not a milestone age, I know, but one that I do seem to have a bit of an issue with. Up until now I have dealt well with the idea of being in my thirties because I was in the "early thirties" age group, like some kind of twenty-something hangover. But now I have most definitely hit that "mid to late thirties" and have suddenly realised that I am as close to fifty as twenty!