Hi. I recently noticed a hard, bony lump toward the top of my forehead, behind my hairline. It feels like bone, and doesn't move; nor does it cause me any pain. It is, however, not present on the other side of my head and this of course leads me to worry. It's not awfully large, for example it can't be seen through the hair. Maybe slightly bigger than a knuckle? Is this just a bone spur, or should I be worried?