I just got a Minolta XE-1 with a nice f1.4 lens on it. After I put new batteries in it the meter started working and I could advance the film (no film in camera) and fire the shutter. I did this several times and then I tried the self timer without advancing the film. Now the film advance lever does not return and I cannot fire the shutter and the self timer does not go back to its original position. Is there a simple fix to this I am missing or will I need to disassemble it?