Carolyn,
I'm reading this post kind of late, so I'm sure you already handled your self with grace and style. I'm wondering how it went for you.
I just wanted to add that I can so relate to this, and I give you so much credit for continuing to sub. I subbed for an instructor at my gym who also teaches the same thing every week. Well, when any instructor even walks in the class and announces that she is a sub, people walk out...and this is okay!
When I sub a class, I am normally familiar with the intructor's routines, and I do try to incorporate my Step routines so that it is the same bpm as the original class. With that beign said, YOU KNOW as an instructor that we cannot please everyone. As long as you were teaching at the posted level of the class, I wouldn't worry too much. The people who are, IMO, in a rut and don't like challenges will always be unhappy. And, as you experienced, there will be some that are happy for the new challenges.
I know it's hard to deal with the rudeness!! When people are talking and being disruptive in my class, I normally make a point to stare at them, and that normally works. I have a friend who actually went up to some disruptive people in her class, during a water break, and said please keep it down...this is MY show...haha. It did shut them up.
It's amazing to me that people are rude when there are subs for classes. You would think they would be happy that someone is subbing so that the class is not cancelled and they can still get a workout. But, is a workout what they truly want? Sometimes, I'm not so sure myself.
We've all been there. It is tough to deal with but you know you are not alone!!
If you get a chance, let us know how you made out?