Quote from Scarecrowi had similar symptoms, so to me this screams "lack of regular exposure to sunlight combined with lack of frequent physical activity".
sleep apnea would cause those symptoms too, or minor depression, or a shitload of other things. we probably shouldn't play doctor based off of four extremely common symptoms.
but then again, he's the one asking an animation community with an average age of 15 for medical advice, so the only helpful advice we can give him is "stop doing that".