Some keys don't work, nothing wrong with the keyboard.

Ok guys so I have this huge problem and I would be eternally grateful if someone helped me. My laptop is the 10.5 inch vaio ultrabook pro 13 touchscreen with windows 8.1. It's hardly two months old and was working perfectly until last night. I've spent hours trying to fix it but I can't seem to get it right. The touchscreen works fine but I somehow messed up my keyboard settings and now half the letters of my keyboard don't work and neither do the backspace the esc and the delete. I'm sure it's not a hardware problem though cause none of the keys were functioning in the beginning and I did something and made some of them work. It's frustrating and I've already checked in the BIOS and there's nothing. I thought it was a NumLock issue but I don't have a NumLock key on the keyboard and my setting in regedit is in 0.

please , if anyone knows something let me know, I'm pretty desperate. Any advice is appreciated.. thanks