Brief Answer:
Tension type headache more probable.

Detailed Answer:
Hello XXXXXXX

I read your query and I am sorry about the symptoms you are experiencing.

I might have been helpful if you had provided some more details regarding your age, other medical conditions, time of onset of the pain, duration of the episodes, frequency etc. Medicine can be so complex and since we don't have the luxury of being able to physically examine you, any seemingly insignificant detail might turn out to be helpful.

That being said the description of "a thousand worms" you make looks more probably to bee related to tension type headache. It is the most common type of primary headache (primary meaning with no identifiable cause), often triggered or exacerbated by stress and anxiety. Usually symptoms are controlled by over the counter pain killers like Ibuprofen, rarely when they are very frequent preventive regular treatment with amitryptiline is used.
Another possible cause might be occipital nerve compression/irritation which is related usually to degenerative changes due to age and trauma in the spinal column leading to compression of this nerve as it exits from the upper part of the neck to innervate the back of the head. Physical therapy and pain killers are the initial management here as well, if not effective at times nerve blocks are tried. The above mentioned amitryptiline can be effective here as well.

I remain at your disposal for further questions.

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