Brief Answer:
Various benign causes

Detailed Answer:
Hi and welcome to HCM

There are many possible causes and most commonly this is caused by migraine attack, tension headache or hypertension. Also, anxiety, whether changes,stress and unhealthy diet may contribute. Some other less common but more serious disorders should be suspected if there is associated dizziness, loss of balance, vision disorder or if pain increases, not improving to painkillers. Also some local skin disorders can be considered such as herpes or dermatitis if there is skin change in painful area.
Please provide more details about your symptoms and any other symptoms that you may be having, so that I am better able to help you.

I suggest to take nonsteroid painkillers, rest, avoid loud, smoky spaces and lights, drink plenty of fluids and avoid watching screens. If it doesn't help, you should see neurologist.

Wish you good health. Regards

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