I can't believe noone has posting the old joke about this. Anyway, what you do is stand in the middle of the dance floor, wait for a break in the set and then scream "I need to be ****ed RIGHT NOW".
If you are a guy you will be kicked out (or arrested). If you are a gal (and reasonably good looking) there will be a queue of guys to choose from.
Good luck.
Second thoughts can generally be amended with judicious action; injudicious actions can seldom be recovered with second thoughts.
--Cyteen by C.J.Cherryh