I really messed up my sleeping schedule!!

It started when one night I was watching a long movie, and when it was over I realized it was almost 4 am

So naturally, I woke up late that morning, but it kept going, then I was up late again that night..etc.

It's been about a week, and it's still going on, I always try to go to sleep early, but because of how late I got up, I can't!

It's almost 5am right now

How am I suposed to fix this?