For about a month now, I have been feeling a heat sensation at the back of my head and neck, and feeling very hot at times, causing me to sweat even when the weather isn't hot. Two weeks ago I suffered from severe headache. Upon getting a blood pressure checkup, my PB had shot up to 150/100, after which I was prescribed with the drag Nifedipine. I took the drug for 7 days and afterwards stops because I felt better. The headache disappeared, but I still have the heat sensation and sweating at times. What could be the cause of this, kindly advise.