I am soooo tired

I hear this happens to everyone, but I am sooooo tired. All of the time. I don't seem to be particularly hungry, or sick, but boy am I worn out. I went to the gym today, 35 minutes of cardio and did some abs. I'm afraid of just letting myself go. I don't want to over do it, but I don't want my weight gain to get out of control. I feel better after working out too. I should be able to fit at least 30 minutes of light cardio and a few minutes of weight training each day. I'd say that it will help me sleep better, but i don't need any help in that department. ~misty