Just learned a valuable lesson with my Nikon F5 - ensure the custom function is set to auto rewind when the end of the film is reached! I just opened the back of mine for like half a second forgetting that the film hadn't been rewound!
My question is, is there any point sending it off for development now? I opened the back indoors at about 18:00 this evening. There was no sunlight in the room, but it was daylight lit. Will the whole film be screwed or might it only be the last couple of frames? The film is Fujifilm Astia 100F, 35mm.