Large painful bug bite swelling in my leg, how do I decrease swelling?

I just moved into an old dorm with bugs, that I was stupid enough to not vacuum. This morning, I noticed a swelling in my leg that itched, but I ignored it. I proceeded to go about my day as usual, going to classes and what not, wearing skinny jeans. I went to the gym afterward, and noticed it was hard to bend that leg when using the rowing machine and as I was walking back I could barely put weight on it. In a matter of few hours, it has swelled to the size of my palm, but worse, its hard to walk. How do I get rid of the pain and swelling? I am not sure if I should go to the university doctor.