When I'm out of college on breaks I often have a heard time getting to sleep at a normal time-i.e. before 12 AM. Therefore, I often find myself waking up around 11 AM or 12 the next day, and increasingly often with a headache that is quite painful, that lasts throughout the day, and is hard to get rid of.

So I was wondering how I can solve the first and second problems I mentioned? Additionally, I was wondering what causes these headaches that feel similar to a hangover when I get them? As I read somewhere they are caused by dehydration during sleep or fluctuating serotonin levels in the brain.