I used to get cluster headaches and I think they were caused by either (a) high BP, which I had... OR (b) a strained neck. I would wake up with headaches if I slept on my sides. My wide shoulders made my head hand at a weird angle I guess. These were bad, bad headaches... like migraines. Yours sounds like a BP issue, though. I agree on dropping the ephedrine. And go see the doctor, too...