I picked up a Pentax MG at a flea market the other day, and it worked beautifully for one roll. Today I tried to load a roll, cocked the wind lever once, then the whole thing locked up. The wind lever has no resistance, it's just loose, and the mirror is locked in up position. I can't depress the shutter button, or anything. does anyone have any idea whats up with this? edittt never mind, I somehow fixed it.