I got a Canon AE-1 for christmas. It was purchased from Jessops and seemed in good condition. After minimal use (10 exposures) It stopped wotrking. The shutter would not fire and I could not advance film. I took it back to jessops and ended up getting a Canon A-1 as replacement. Now after having taken 4 exposures with the camera the exact same thing has happened. I am aware it could just be chance that it has happened but I was wondering if it could be something else. Is it possible I'm doing something that is causing it to happen? I do not mistreat the cameras in any way.