It's astonishing how often migraines are caused by sternocleidomastoid muscle tension that can be relieved by massaging it just right. There's a Tumblr post detailing this, in case it works for you. FML isn't showing my comment with the link, but a web search on "The first is the sternocleidomastoid muscle" (with the quotes) will get you there. (If you've already tried this, then I apologize for mansplaining.)

I suggest seeing a neurologist if you can do so. I have occasional migraines myself and know how miserable they are. I inherited that from Mom… I have found that that for me there are multiple factors that can result in a migraine. And even there it’s rarely absolutely clear what triggers them. I have found that some medications caused a significant increase in migraines such as Flomax and some foods cause a higher likelihood of getting a migraine - The worst for me is cured meats containing nitrites or nitrates such as most bacon, ham, and salami and other cured meats. Finally, for me stress is a trigger for migraines. These factors seem to be additive. I can have the occasional sandwich with cured meat and usually not get a migraine. But too much cured meat or add stress to the equation and the chances of a migraine get bad.

can you do exercises recommended by the physio at home / with a friend? I've also found youtube can be helpful when trying to learn a new exercise

Hello one of 3 things it could be. 1.) sleep apnea snoring 2.) heart regulation issues or 3.) you need to have your hormones checked for thyroid levels.