I had splitting headaches every morning for the first 3wks. Just keep drinking the water (you will lose loads during workouts), eat well and take a good multi-vitamin. I think our minds and bodies are so shattered due to the relentless abuse over the years.....they're tired and want rest....time to recover. So yes, headaches are 'normal'....our little nerve endings are screaming, having just started to wake up from being numbed for years x