You were thinking about it when you were 24!!! I don't have a problem with being 30, most of my friends are 30 or older, it's just bizarre to think about considering how old it seemed growing up.
my wife tries to annoy me by reminding me of how close I am to 30 (I'm 29 on Monday), but I can always get her back since she's getting awfully close to 40 - now that's much more terrifying. 30 ain't shit.