Photoshop has corrupt my file, can only see blocks and lines

I was working on a file and after copying and pasting (I think) and then this happened

I tried copying and pasting all the layers to another file but it just copies over the corruption as well. I'm afraid to save the file or close Photoshop in case I lose my work because, obviously, I haven't saved in a while.

Has anyone else experienced this issue and is there anyway to fix it or should I just accept it's lost forever?

I'm using Photoshop CS5 on Mac 10.9.