It is a common story. You haven’t slept well for three days now. The alarm is set for 7 a.m. You get into bed early, hoping that tonight you’ll fall asleep early and stay asleep. Instead, you wake up at 2 a.m., staring at the ceiling, wide awake, frustrated and worrying about how you’ll function at work the next day. It takes more than two hours to fall back asleep and, before you know it, the alarm is blasting and a new day begins.