Chiaroscuro

Is it a sleep disorder? Do you . . . - feel irritable or sleepy during the day? - have difficulty staying awake when sitting still or reading? - fall asleep or feel very tired while driving? - have difficulty concentrating? - often get told by others that you look tired? - react slowly? - have trouble controlling your emotions? - feel like you have to take a nap almost every day? - require caffeinated beverages to keep yourself going?