Brief Answer:
Tension type headache

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

That type of pain after evaluating its description and its association with anxiety seems to be what is called a tension type headache. It's the most common type of primary headache (primary meaning with no identifiable cause) and it is frequently triggered or exacerbated by stress and anxiety.

If the episodes are rare than only the occasional pain killers like Ibuprofen are recommended. When they are frequent though, associated with chronic anxiety, then preventive treatment is considered, usually with antidepressants which are also anti anxiety medication. Options may include group of tricyclics like amitriptyline, more proven in headache prevention (but can cause side effects like orthostatic hypotension which warrants care when used in the elderly because of the risk of falls), or SSRI class like citalopram which have fewer side effects.
Benzodiazepines like Xanax are not suitable for long term use because of their potential for dependence and tolerance.

Also relaxation exercises, light physical exercise, activities like yoga can also be effective.

I remain at your disposal for other questions.

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