What are these lumps?

Patient: Underneath the skin on both sides of my jaw are lumps. They start off painful and sore, and I can rarely pop them. Some disintegrate under the skin into lots of little bumps, but for some it is obvious they are filled with something, others are not. These types of bumps only occur on the skin between my ears and the corners of my jaw. I exercise regularly, eat a reasonably healthy diet (vegetables, meat, fruit – all good quality), rarely smoke, drink in moderation, do not take drugs, am sexually active, get around 7-8 hours sleep a night (which I can cope with) and do not have prominent acne except on my back. I am 16 years old and male. Thanks very much.

Doctor: