How to completely turn back on my phone

Might be an issue with some sort of software that's keeping it in a loop?

You could try turning it on in safe-mode. Each phone has it's own way of initiating this. This link is for a samsung galaxy ace I. It might be the same for a ace II.

http://forum.xda-developers.com/showthre...

Once you're in safe mode, I'd try to clear out any apps you think could be causing an issue (any apps downloaded right before this happened, app that has crashed a lot before, etc)