After a long and tiring day at work or school, you go home and rush to your bed, thankful that you can finally rest. But just when you’re about to close your eyes and go to sleep, you feel a sudden pinch of pain in your head. It started as a small, tolerable pain, so you just ignore it. The next thing you know, you’re already enduring a splitting headache that keeps you up all night. And the same thing happens again the next day. And the next day. And the next day.