Brief Answer:
Supportive care

Detailed Answer:
Thank you for asking

I read your question and i understand your concern. Headache at back of the head with jaw involvement is a very wide and versatile symptom and can cover hundreds of possibilities. Commonest ones are tension type headaches, migraines, sinuses headaches, anxiety and depression or muscle spasm due to poor posture during sleep. I would suggest take some advil, some skelaxin and rest for a while and see if it helps. If there is some recent cold or flu history or pain in ear in the past then seek an otorhinolaryngologist. if the headache is associated with some vision problem or anxiety neurosis then seek a neurologist.

Nutshell, most of the time headache self resolves with slight supportive care and should not be worried about. I hope it helps. Take good care of yourself and dont forget to close the discussion please.

Regards
Khan

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