I have a lump on my head. it's hard,immovable and doesnt hurt when touched. i think its bone but will it be a problem?

Please repost: Please repost and describe WHERE on your head it is and how and why you think it’s “abnormal.”

Hard to be specific: The skull will occasionally form calcium deposits after local trauma that will take the form of bumps. Above the brow is a common location but any site may be involved. This is due to a repair process triggered when trauma scuffs the skull surface. These may or may not disappear over months. You would need an exam to decide whether x-rays might assist diagnosis.

Exostosis: If this bony lump has been present since birth, it could be a benign outgrowth of bone(exostosis) that is larger as you grew older. Of course, a physician would have to examine you for accurate diagnosis.