What incident shows how immature Nora is, in the play?

One part of the story which shows Nora's immaturity focuses on the varying ways she "cheats" on her husband, who expects her to live up to a particular image that he has created for her. She, for example, eats macaroons when he does not want this to happen and then lies about that eating. Another example of her "rebellion" occurs when she swears, doing something that is normally not proper for a woman of her status.