Your film is toast, unfortunately. Do as the others say and develop it, hope for the best and expect the worst.

On the manual bodies, it is possible to feel on the rewind lever whether there is a film in the camera. It will turn very freely if the camera is empty, and will feel stiffer even if you are just taking up the slack in the cassette, and will stop when all slack is taken up. You will also hear the film creaking while you do this, if there is any in the camera. I always do this before opening up a manual body. If I am unsure, I open in the dark or in a changing bag. I am so paranoid about this that I specifically wind back until all the slack is taken up inside the spool. Then, when I wind on the film, I can see the rewind lever turning with the spool as it moves inside. That is 100% positive indication that film is loaded.

This is learning from others' mistakes, as well as my own. I had a friend with me while we were photographing wildlife, and had an incredible scene. My camera had film loaded. He thought his had. I have on other occasions either shot an entire roll of virtual film, or opened up a camera with film inside. However, it's a long time since I last did anything like that.

Good luck though.