Brief Answer:
More information might be useful

Detailed Answer:
I read your question carefully and I understand your concern.

I wish you had provided some more detail about the headache and its history though, there are many causes of headache, often difficult to identify, so at least a detailed history is needed.
You mention only the sharp character and the side of the pain. Some more details you could add are:
- its location,
- possible triggering factors (chewing, speaking,lack of sleep, alcohol etc)
- duration of the pain episodes (how many minutes/hours)
- frequency (how many episodes a day/week/month),
- since when have the painful episodes started
- accompanying phenomena like eye redness, tearing, congested nose, skin color changes, nausea or vomiting, vision changes etc, anything may be useful)
- other medical conditions, medications or tests you've had.

For the moment I can say that causes of sharp unilateral pain may include trigeminal neuralgia, occipital neuralgia, temporal arteritis, cluster headache, paroxysmal hemicrania, sinus/ear/tooth infections, temporomandilar joint dysfunction, etc. Perhaps might be able to exclude some of these once you provide the above information.

Looking forward to hearing from you again.

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