Cloud auto-saved file but I need to recover old version

I have been working on a multi-layer project in Photoshop for several days. I'm working on my iMac but the entire project was in the cloud.  Today, I needed to save it on my computer as a smaller jpg file instead of the PSD.  I changed the file size to save as jpeg but when I tried to go back to the original file, the cloud had auto-saved it at the much smaller size.  Now I can't find any way to retrieve the project in its original size.  I tried going to cloud to find it, but the cloud says I have no docs.  Please help!!  That was a lot of work to lose.