I saved my powerpoint project in removable disk!!!?

just a few minute ago, my twin and I had struggled try to finish our school project using the Microsoft PowerPoint. it takes hours to make it..but then, when I tried to saved it in our pendrive, the computer states there that the powerpoint can't be save in there..but i had closed it already..when i opened My Computer, the pendrive shows removable disk..and that means i had saved in the removable disk, not in the pendrive.each time i try to open the PowerPoint project, it says that the computer can't open it...ohhhh..please help us!! it is a competition and we had to gave it to our teacher as soon as tomorrow.. :'( please, anyone!ANSWER THIS QUESTION AS FAST AS YOU CAN..please don't say about the unfortunate side..!!!! I CAN'T THINK of ANYTHING RIGHT NOW!!!