Lost all contents of My Documents How to recover?

I am broke virtually. I have lost so many reading materials which I had printed into pdf, many freeware, and least importantly songs and other downloads. It wa all fine last time I turned off my computer. Now there is nothing other than sample pictures and music. It looks like I have created a new user account. Can anybody seriously suggest me to recover the files at least? I am really worried because the lost data included my brother’s thesis input data as well. He had stored a few hundreds xlsx documents and are now under threat. Can anybody soon throw us some help light?