File Invalid but nothing anyone has said as helped!!!

I spent nearly two hours on a score, and I saved it before I closed my computer as I do, and I returned a few hours later trying to open it, when it says it's invalid. So naturally, I came here, and I tried numerous things people have said have worked for them (like searching through backup, searching through hidden files) and when those things are suggested, people always say "Oh, thank you so much! I found it! It worked!" but NONE of those things have worked and my score is still gone!!! I'm on the verge of tears because I worked SO hard on this and I'm starting to think it's really gone!! I found a post with a list of files to search and I tried every single one of them and all of them cam up with no results in my files app! What do I do!!! PLEASE HELP.