I m a 22 year old female. 5 9 around 140 lbs. I have no serious previous health issues. Lately, I ve been feeling very shaky and antsy. The only way to describe it is the way you feel after drinking too many energy drinks. Very shaky, feeling like I should be active, but also feeling too tired to do so. I haven t had any caffeine and I ve been eating relatively large and healthy meals. My period is a few days late, but that s not out of the ordinary. I m not particularly stressed and I m not feeling any other sickness symptoms aside from a mild headache . I ve also had some serious muscle cramps , especially in my feet and calf muscles. Often while I m sleeping I will wake up in pain. I have been drinking a lot of water, taking vitamins , and eating bananas and grapes to try and stop it from happening.However, it could be that I work long hours and I m constantly on my feet. Any ideas?