insomnia can manifest in single episodes that are long times between. I do have Periodic Episode Insomnia, so I know what it's like.
However you could be stressed out, having a psycological paralel relation between your bed and some bad experience that is only now manefesting, OR you could have eaten something bad a few nights ago that is still in your system and causing you sleep issues.
Early waking huh? That looks more on the diet part (eating something bad). Try going for a run, not eating meat for just the day, drinking a glass of water an hour before bed and putting an extra blanket down between you and the mattress. It wouldnt hurt to go for a long run during the day also, as that will serve multiple purposes. Running will tire your body and mind so you will feel like sleeping mre, it jump starts your digstive system to get rid of more waste and whatever is in there, and is relaxing in the long run if you like where your running. so find a good day in the week and...
Go for a long run.
Eat full servings of veggies, bread and fruit, and go without meat for a day (or two)
Drink plenty of water that day.
Put an extra blanket on mattress to sleep on top of.
Also if you have a habbit of frequent personal sexual activity you may want to hold off during this time and just see if that makes any difference. That's probably not something to worry about but there's a chance of connection.