Brief Answer:
Tension type headache more probable.

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

Looking at that description, with switching of the pain areas and short lasting episodes, I do not believe that sinus headache is the cause, the pain would be much more consistent both in location and duration.

I must say that type of pain is not consistent with common pain syndromes, do not fulfill the criteria for a certain diagnosis.
The most probable alternative would be a variation of tension type headache, the most common primary headache (primary means with no identifiable cause), exacerbated by stress and anxiety, which commonly can have moving abnormal sensations in the scalp.
If the pains are more concentrated on the posterior part of your head it may be related to cervical spinal issues which may cause irritation of the cervical nerves innervating the posterior part of your head.
The treatment for both those conditions remains the same though the Ibuprofen which has already been recommended.

While I imagine I may not sound very determined in my answer one thing I may say with confidence, that those pains, in the absence of other symptoms, do not correspond to any type of threatening brain lesion, such as stroke, tumor, infection etc, which might require emergency evaluation.
If there is some other symptom you didn't mention, previous history of this or other types of headache, or some other condition you are known to suffer please tell me so that I can re-evaluate my opinion.

I remain at your disposal for further questions.

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