Aww, it is scary to turn 30! I just did it this year and before it happened I was freaked out and felt sooo old. Especially since I'm in grad school with 22 year olds all day.
But then my birthday hit, and it was awesome! I realized I'm in the youngest part of my thirties. That feels way better than being in the last part of my twenties!
And now when I hear the 22 year old drama at school I get to think "thank goodness I don't have to deal with that anymore--I'm 30 and grown."
Hope you feel that way after your bday, too!