Why

Why is it that if you go to sleep with a headache, it's still there in the morning? Or does this only happen to me? And not only did I wake up with the headache, but I felt like I hardly slept at all. I am exhausted. I am fairly certain that both are caused by lack of caffeine. I decided yesterday (after having a coke in the morning) that I have to break myself of the caffeine habit. I did so well for so long, only having caffeine once a week or so. Then my frappuchino habit started and on the days when I didn't get one of those in the morning, I'd have a pepsi with lunch. Well, no more. I feel better when I'm drinking mostly water and next-to-no caffeine filled drinks. So after just the one small one yesterday morning, I'm sure it contributed to the headache and tiredness this morning. But I'm determined to do this. Just one little baby step towards feeling some control over my health.