I feel like I'm wasting my college life

People say college is the best time of their lives. I'm a junior in college. I haven't been to a party yet. I don't have a core social group, just a few individual friends. I feel like I should be partying atleast once a week. I've seen big groups of students hang out in the dining hall. Lots of people like to have things like barbecues. They go to football games, they hang out at the mall, smoke weed etc. I haven't had a core group of friends to do stuff with since being here (I did in highschool but I dropped them because they were shitty people).

I don't know what I'm doing wrong. I'm introverted but not socially awkward. I am a CS major so a lot of the people in my classes are socially awkward + autistic traits. I'm trying to distance myself from that. I switched dorms so I can live closer to the liberal arts majors. I really make an effort to interact with my roomates and neighbors and people. I joined a martial arts club. I say hi to people in the gym. I also have the advantage of being a not-ugly (but a bit nerdy) female, which should make it easy to get invited to stuff. I guess I don't really get out much unless it's to go to class. I live on campus but I even go home on the weekends. I'm from a commuter college so the campus clears out on the weekends. I know I won't leave my room if I don't have class to go to so I just go home.

Tldr: How do you find a core social group that likes to do cool stuff