I get a tingling sensation, usually on the left side, sometimes the whole left side, other times, just the left side behind my ear. I have attributed it to a circulation issue caused by inflammation in my upper neck. It is a surface tingling, as if it is the skin or just below the skin. Similar to the tingling you feel when walking into a cold area.

I have learned to try to ignore it. It has never caused any other problems.

btw, Circulation on and in the head are symptoms of concussion when the vascular system has lost some circulation controls temporarily. The circulatory control system in the head is very complex and sensitive. When they do functional images of the brain, they usually track blood flow or metabolism. The blood flow will slow to some areas and increase to others.