Thank you for writing. I hope, I hope you have talked to your medical doctor about this. You may be right this is a symptom of anxiety. But it’s also possible that it is coincidental that a disagreement seems to trigger it. Headaches like you describe are not something to ignore.
I don’t agree that there isn’t a real problem — whether it is medical or stress. Pain is a way that a person’s body signals that something is wrong.
I think you are used to being self-sufficient and able to take care of things yourself. But one of the most important ways we can take care of ourselves is by knowing when to look to others for a little help. If your medical doctor doesn’t find a cause, do see a therapist for a few sessions to figure out why the ways you have managed stress or anxiety in the past are no longer working for you. A therapist can also help you learn some new ways to help yourself.
I wish you well.