Accidental deleted folder! can I retrieve?

I uploaded some files to a folder (large ones), once they were uploaded I renamed the folder. When I did SmartFTP just seemed to create a new folder with the new name.

So I just deleted it, not realising that it had actually renamed it, but for some reason kept the old folder name on display aswell. So I deleted all my files.

Is there any way I can "undo" this action? I have the files on my HDD ofcourse but they took some considerable time to upload.