I was working when I switched to another project. When I went to switch back, this error popped up. In my files there was only a 3 day old version and in my Autosaves there was only one (which was 2 days old)
The render I exported for this project is also gone.
Without any specific info about your system, where you saved your projects and other details we can't really tell you much. that said, chances are nearly non-existant that you can recover anything. If the save went wrong and AE didn't even throw an error, then something seriously bad happened.