Hello I am a 46 year old man and for as long as I can remember I have noticed on each side of lower head you have a bump, but my left side is larger than the right and has been for as long as I can remember now that I wear my hair short you can see it protruding like a small tumor, its hard and does not move, it feels like skull and I wear a ball cap a lot and it rubs there, I have had no medical problems from this that I know, however I plan on bringing it to the doctors attention, has anyone out there experienced this???