It is most likely just a pimple or hair follicle that is infected (folliculitis). Residue from shampoo, conditioners, or even oil produced by your scalp can clog the pores or hair follicles around your ears and cause this. It will most likely go away in a week or so.
Sounds like a pimple, stop touching it. By touching it, you introduce new bacteria to the area. If it is exposed, disinfect and keep clean. It should go away in two to three days. If not, see a physician.
It might just be a zit. Put a hot wash cloth on it for a while to help clean it out. If you notice it continues to get larger and doesn't pop like a zit, go to the doctor.
