Woke up at 5 am today for no reason, after only 4 1/2 hours of sleep. Tried to get back to sleep, but no luck... after a while, I just gave up and started my day.

I understand waking up if you're dehydrated, or if you're over-hydrated and have to use the restroom. But waking up for no reason... ugh, not sure how to fix it.

Do you ever go through phases where you wake up early for no reason? Any ideas on how to fix it?