Tired all the time, drinking a lot of water, dizzy, shaky, headaches. I am male and 18 years old. Lately I ve been feeling extremely tired and drinking a lot more water than I normally do. It seems like every time I drink I just get more thirsty. Every time I ve gone outside in the cold (always below zero because of where I live) my arms and legs shake a lot, and my hands turn bright red. I m really skinny so that might have something to do with it, but I m always bundled up. I ve been getting a lot of headaches as well, and my heart rate is always extremely high. I smoke cigarettes, but not an excessive amount. I m not sure what it is, but it s getting pretty annoying.