I have a USB. When I plug it into the computer, the contents of the USB don't display.?

I have a USB drive. I have data on it - music, programs and pdf's. When I shut down my computer last night, the USB seemed to be working fine. Today I woke up, started my computer, put the USB into the computer, and when the contents of the USB showed, were a bunch of folders and other files that were were written in Russian or Ukraine or whatever skribble was that. And then the letter of the USB was written normally but beside that were skribble letters of some kind. So I tried renaming the skribble with KINGSTON (G:). And when I did, the contents of the folder disappeared. But when I clicked on properties, it showed me that 13.5 GB are used, and 3.50 GB are not. I don't know what to do to get my data back ! Please help.