Brief Answer:
Some possibilities listed...

Detailed Answer:
Hello and welcome to HealthcareMagic. I read your question carefully and I understand your concern.

Given the intermittent nature of the headache I would say that brain lesions (such as stroke, tumors, inflammation) are not likely. I would look into other head structures. One possibility would be an ear infection which given the location you mention would be the first hypothesis to be excluded.
Another possibility would be that of a temporomandibular joint dysfunction, the joint between your mandible and the skull which could manifest with pain in that location as well.
Temporal arteritis (otherwise called giant cell arteritis), inflammation of a superficial artery in that area could also present with unilateral pain. I wouldn’t think it that likely for your age, usually after the age of 60, but a simple routine blood test called erythrocyte sedimentation rate (ESR) might be done to definitely rule that out.

So I would start by consulting your primary physician, for a physical exam including examination of the ear, temporal artery palpation and testing temporomandibular joint, as well as a routine blood test, blood count and ESR to check for white blood cell changes related to infection and inflammation.

I remain at your disposal for other questions.

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