Flashdrive ~$WVFBC.FAT error

Hello,





I was using my usb drive in my sister's laptop when her antivirus detected a worm virus and without a doubt, i deleted that file not knowing it was a .fat file. as soon as i open my flash drive it says "There was a problem startjng ~$WVFBC.FAT" There are important files in my flashdrive and I don't have any extra copy for that. Can anybody answer my problem?
I keep installing data recovery softwares but they keep asking for serial's and i can't afford. I'm 14 so please help me.