If you really can't see any physical difference, then this is a learning experience. You'll just need to process all the rolls.
You'll probably figure out a way to mark your shot film in the future. I always left the leader out (as you did), but tore off the end to mark the shot film. You can fold it over, mark with a Sharpie marker, wind it all the way in, put the film in the can upside-down, put tape over the end of the film, put shot film in an envelope or plastic bag, etc.
The key is to do this consistently, of course.