I was getting into my car and hit my head hard against the top of the door frame. I got dizzy and almost passed out, but was able to hold onto my car. It left an indentation on the right top side of my scalp. The area keeps getting a scab which won t go away. I also get some soft blisters that go away. This happened about 4 months ago and I did have a doctor look at it. I had a few areas treated that were pre cancerous. These blisters come and go. Lately, I have had headaches from my lower right side of my neck up to the area where I hit my head. Every time I see the doctor none of these blisters appear. Thirteen years ago, I had a level 4 Melanoma on my right muscle. I get a little nervous when I can t understand what is happening to me. I m over 70 years old. Any thoughts.