To combat cramps, take calcium -- it works like a charm! My SIL told me about that for leg cramps during pregnancy (she had to take 2-3 tablets every night or have horrendous leg cramps), so I tried it during my next pregnancy, and then tried it for other muscle aches including menstrual cramps, and it works!
Please don't take feeling crappy for 75% of your life as being normal! Check out the Blood Type Diet (http://www.dadamo.com) for information on what foods are best for your blood type. You may have some particular deficiency ("exhaustion" makes me think you might be anemic, as an example); but since being on the BTD, I've noticed significant improvement (and have lost 15 lb, which never hurts!), and MANY people on the BTD forums and diet will say that their moodiness changed when they changed their diet (usually stopped eating wheat and/or corn, depending on their blood type).