It is best to speak up. Especially if you are going to write about it later. She should be given a chance to rectify the situation. If she reacts negatively, definitely write a review about it.I've had a couple girls, mid session, I told to go clean up. No problem.
One of my favourites told me she'd rather I be honest and speak up, rather than hear about it later.
One time I didn't speak up, I was too embarrassed, didn't want to embarrass her, and told her later. That didn't go over well.