Why am I suddenly nervous for the pre-prom meeting?

I wasn't at all before this. Even ten minutes ago I was fine. Now suddenly I'm nervous. I don't even know why. It definitely isn't because Adam and Josh and their parents are going to be there, along with my mom. I wasn't nervous about this before, because I'll just be me and apparently people like me. Still, suddenly nervous. I have to start getting ready in a half an hour. Until then I'm doing homework. I'm going to go check to make sure my prom ticket is still in my car. And the lovely girls in my class who were manning the ticket sales spelt my name wrong, I mean come on, it's not like I've been in the same class as you for 5 years. Alright, back to my spanish story about a unicorn.