Hello....your symptoms match the profile of a hypochondriacal disorder...these people frequently fear that something is wrong and some underlying disease process is going on in their bodies. All investigation comes normal but still they fear...sometime fear shift from one to other. These people want to get investigated for various illness.. My question is , do have any problem in your scalp
except feeling a dent which you found incidentally while you were exploring and later on became tense due to that. If answer is no...than you have to learn to let such things go and not to worry so much....because if this persist you may be progressing to a chronic illness and you may face lots of problems due to that.