Go dude, it'll be fun. I had a "I don't give a f*ck" attitude in high school when it came to social events like that. Didn't go my first three years. Figured, what the hell, I'm a senior, I may as well go. I didn't decide to go until like 4 days before. I'm glad I went. Went with a huge group of people (like 15) to dinner. The reservations were foobared, and we ended up only getting there with about an hour left.
Same with prom. I was a slacker. Decided to go about 6 days before the dance. Heh. That kinda sucked, because it didn't give the girl I went with much time to find to a dress (she wasn't going, she was a sophomore), but we had fun anyways. Didn't have a limo, just drove my mom's Crown Vic.
Good times, good times. You only live once, do it to it.