1- Hopefully its not cancer
2- Just go see a family doctor first before jumping to conclusions. They can prescribe you antibiotics to see if its just an infection that will go away. A checkup should cost anywhere from 50-100 dollars. It isn't a lot if you think about it.
3- If you are enrolled in college you paid for mandatory health fee. Go visit your school's health office. They will be able to look at it and maybe prescribe antibiotics.