the college health center referred me, in a super-weak, light-headed state, to an oncologist.

This basically happened to me once. I went to Drake (the clinic at Auburn) with these weird lumps on my arms. They immediately said "well, we need to stick you with this big needle, drain one of those and see if it's cancer. Being young and full of I can't have cancer, I'm only 19, I went to a real doctor the next day. Turns out it was cat-scratch fever. A fungal infetion of the lymph nodes cause by actually being scratched by a cat with this fungus on it's claws. What's the cure for cat-scratch fever? Nothing. Wait it out. It took 2.5 years, but they went away.