I can empathize. I feel uncomfortable at parties and nightclubs, mainly because I hardly go. I bet if you went once a week for a year, you would feel more comfortable.
I have never been much of a party-goer and I don't care for clubs anyway. I think its a good thing that you are more of an introvert. Too often, doing "fun things" seems to involve clubbing and whatnot, so its to hear that you are different.
If you want to change, simply go to parties and clubs more often. Generally, the more you do something the more comfortable it is.
