Since the pen drive is FAT formatted, you might find the best undelete tools for it are for Windows. I can't suggest a specific product, I'm afraid, but googling "undelete usb pendrive" brought up a few promising-looking links (almost all for Windows, of course).
I honestly don't know whether there's a FAT undelete program for Linux. Hopefully someone else here will know more on that. Deleted files on a FAT FS should be reasonably simple for an undelete program to recover.
Whatever you do though, don't save anything else to the device until you've tried the undelete process.
One other thing to check before you panic is your desktop trashcan, on both the Suse and Windows machines. You might even get lucky and find your files got put there. Would depend on how you deleted them, of course, but it's worth checking.
Hope that helps