Being a first grade teacher, when I don't want my kids to move ahead there are things you can do. One, for example, is to pair yourself (being advanced in this class) with someone who is struggling. That way she just doubled her chances of moving the rest of the class to where you are. I'm sure you would have been happy to help someone even though it's not your class. She should have played with your strengths and not shot you down for them. I'm sorry you had to go through that. How frustrating. But it sounds like you handled yourself with dignity and honestly, I don't know what I would do in that situation. I am snarky and probably would have said something equally as rude right back to her... in a joking manner so feelings don't get hurt but she still knows that she was out of line.
So are you finished with the class or do you have to go back for a few more classes?