Tender spot on crown of head

I have experienced a tender spot on the crown of my head since my early 20's, always in the same spot and lasts for a few days, then goes away only to return a month or so later. It is right on the tip top of the crown of my head, feels like a bruise as if I had hit it on something. There is the slightest bit of swelling, nothing that anyone else has ever been able to feel, but I do. It seems to be more pronounced after I have had a few alcoholic beverages. In fact it sort of throbs and hurts if I even raise my eyebrows. Any suggestions as to what this is. I am now 33 years old and it has been happening for many years now, so I am not exactly afraid that it may be life threatening. I am just curious and was wondering how I would approach this "ghost" of an issue with my doctor since he really can't see or feel it.