Everything has reset

I don't really know where to put this so I'm not sure whether it will be answered here or not but here goes. Basically last night I turned my computer off the same way I have done for the past few months nothing different not even an update but as soon as I log on this morning everything I had is now gone except for the most of my important things on my external hard drive. The personalization has reset, my documents has reset, images, all files based on the computer have just gone back to as if I just bought it with a few links on the desktop for games that I had on the external hard drive, even my %appdata% has been reset and I cannot find a way to put it back to how it was before. Please help me I really don't want to lose all of my files because it has some important work on them.

Thank You
Michael

Did you not create a restore point?
If not check whether it has been done automatically by opening Settings, type sys in box at top and click on "create a system restore point".
Is protection on?....if not click on "system restore" to check if one is available.