Can't boot from bootcamp after sudden crash

Hi,

So today I was playing cs:go, running bootcamp, when suddenly my mac crashed and rebooted to mavericks... I've tried several things on this thread but I still can't boot on bootcamp... I really need some files I have there and I can't access them -.-' Is there a way to fix this and get bootcamp to work again? Tell me what you need from terminal so I can upload it here.

Btw, when I created the bootcamp partition I created it with 100gb and later I upgraded it to 400gb without reinstalling bootcamp but it as worked fine for more than a month so I'm assuming that is not the problem...

I really need some help with this...

Thanks,

Gabriel