I would also wait and see if the instructor made up the time on your next class. If so, then I would just let it go and not worry about getting my money back. Even though nothing has been said by the instructor, it sounds like she is trying to make the time up on the missed class. I would give her the benefit of the doubt.
Oops, didn't see your last post. In that case, I would feel another class is in order to make it up, and if she isn't willing to do that, then I would nicely request a refund for that missed class.