Almost pimple, how to get rid of it?!?

Ok, i think in the UK they call them lurkers. Like a pimple thats big and painful and red, but you can't squeeze it without feeling like your face is about to explode. So i have one on my chin and it hurts, ive had it for about a week, and it won't go away. It wont' turn white or black or anything. It's just a red lump of crapiness that i can't get rid of. Oh btw, i'm starting my modeling classes soon, and we can't wear make-up, so i'd rather not have a big red lump on my chin. Any ideas that don't involve some expensive cleanser or zitzap would be appreciated.