Growing lump on face under skin. 1 week old

I'm 15 years old and about a week ago I noticed a small lump which feels like a hard circular object on my face just to the right of my left earlobe. It appears to be growing, as it is larger then it was a week ago. When I apply pressure to the lump it hurts and is very sensitive. I also have never had any skin problems, and my face is very clear of pimples. Any information on what I should do or what this possibly could be would be greatly appreciated. Thanks a lot.