Microsoft Word Doent Mysteriously Vanished?

I was working on a paper today and I went to save the paper as usual, then exited out of it. About a minute later I went to open it up again and I couldn't find it. I know I saved it but I CANNOT find it. I have searched in all my files. I even downloaded some file recovery software and that didn't work. It's gone. Can someone please tell me how I might get it back or where it went. This was a huge paper I was working on and very important. I can't just redo it. Help would be appreciated. Thank you.