Can somebody help me with this virus in my flash drive?

[joeval]

I bought a new flash drive last week and i had saved files in it for 2 days. I always save file in it using other computer because we dont have internet at all. And every time i plug my flash drive to our computer my file is corrupted even the notepad and msword is not in its right format. All the typed words in the notepad and msword was replaced with this character "ÿ". I've done the same thing again but i always end up seeing the "ÿ" and all the application is corrupted. I asked one of my friends and he told me that there is something wrong with my flash drive and there is something like hidden virus. I always scan my flash drive but my anti virus doesn't detect any virus at all. As what i have noticed in my flash drive, the folders in it are extended with unknown special characters written inside and there are lots of unreadable files and the only thing is that i only saved pictures in the folder and why is it that the pictures are gone and replaced with unknown thing. Can anyone help me about this thing or what should i do to get rid of this matter. Thanks.