Maybe deleted accidentally?! thinking

I was creating a new post @good-karma and hitting the save button as I worked. The screen exited from write mode. I clicked the "pen" at the bottom of the screen & went back in -- all of my work was gone. I wasn't too worried at that point because I had been saving to draft regularly. Then I saw nothing had been saved for three hours and had to redo all my work! Grrr!