I'm glad that you are going to see your PCP. However, when I get a really horrible, awful, wish you could die migraine, I sweat, my face flushes with an almost butterfly pattern across my cheeks. Then I get cold, my hands get clammy and I'm so dizzy I can't walk. So you're not alone. But it's good to be cautious and follow up with the doc.
I had a tilt table test done a couple of years ago and found that I have orthostatic hypotension. What that means is that when I change position quickly, go from lying down to sitting or standing, my blood pressure does a nose dive and my heart rate goes way up. I'm on some meds to keep that from happening as much. However, when a bad migraine hits, these symptoms come back full force. Not fun, just increases the nausea.
I'm sorry you're dealing with this. I know what you're going through. I hope you feel better soon.