Does anyone else feel sad about getting older..?

First of all,it's not like I'm 40.I'll be turning 20 in December and this is really perturbing me even though I know quite well that it's pretty pointless for all of us humans are destined to eventually turn into old farts and die.I know that age shouldn't define your personality or anything,but I feel so used to being referred to as a 'teenager' and I can't believe the teenage is coming to an end.I think I'll really hate telling someone 'Well,I'm 20.'Ew.I look at 16-17 year olds and feel so envious. :| I wish I could go back to that age.And no,I don't believe age is just a 'number'.IT ISN'T! I also know that I can still myself 'Shutup,you're still disgustingly young' but the thing is that time seems to be moving too FAST.Feels like I'll blink my eye once more and then I'll be 25.Scary.I don't want suggestions or consolations or something,but just wondering does anyone else feel that way?Some of my friends do,but not many obsess over age the way I do.I feel I'm gonna be depressed as hell on this b'day,no matter how hard I party.I'm and 'adult' now,sigh. ;(