Youve waited a little too long, but just invite yourself. Text or call or talk to all the people you know, and ask them something like 'know any parties happening this weekend? I need to figure out all my options'
This is actually exactly what I did... And last weekend and this weekend were both packed with shit to do. As long as you have a friend at the party, you dont need to be invited! 'Hey! i'm mike. so and sos friend'