Lenovo g505s problems turning on?

Right i bought a lenovo g505s amd a10 and it arrived yesterday. I installed a couple of games i had on my old laptop so i know they are safe, and i got minecraft pc which was my main reason for this laptop. I also got avg 2014 free edition. I used my laptop all day with no issues at all and before i turned it off avg decided to do a full scan and found nothing.
I've been working and got home and turned it on it loaded fine with the lenovo logo and i signed into windows, it has 8.1. But it just loads to a blank black screen with the mouse on it. I don't know if its something i've done wrong or what, i had windows xp before and had no experience with 7, 8, or 8.1.
I've saved up for ages for this laptop and now it won't work D,= any help is appreciated.
If there's a way to restore it to its original state thats fine as i can just redownload minecraft and avg.

I have that same model of laptop. Isn't there an arrow button right by the power button that puts you into restore mode?

I can do ctrl, alt, delete and the menu pops up and i can access task manager. But there's no windows 8.1 menu screen its still black with the task manager box.