You need to get more sleep:
The surprise is how much sleep affects academic performance and emotional stability, as well as phenomena that we assumed to be entirely unrelated, such as the international obesity epidemic and the rise of Attention Deficit Hyperactivity Disorder. A few scientists theorize that sleep problems during formative years can cause permanent changes in a child’s brain structure: damage that one can’t sleep off like a hangover. It’s even possible that many of the hallmark characteristics of being a tweener and teen—moodiness, depression, and even binge eating—are actually symptoms of chronic sleep deprivation.