For about 8 years be4 I was diagnosed with high blood pressure I knew I had it and every time I was checked at the dr's it would be fine. I got migraines atleast 2 times a month for 3 days at a time. Anyway if it is not high when they check it they say its not there. But the thing about it is, it goes up and down, and if youre like me and had low blood pressure first, then a normal reading for most pple is already hi for you. I found pounding in the head to be associated with my hi blood pressure, cooling off my head with cooler water helps a great deal. And the back of my neck.
I stand on the floor by the shower and bend over let the water from the shower just flow on my head as cold as I can stand, as long as I can stand it. It helps me a lot, especially when you live in humid climate.