During the scene right after "Selena y Los Dinos" finish performing Marcela, Selena's mom, has a talk with Abraham, her father, about criticizing the kids. All during the conversation Marcela's hair looks different each time they show her. Sometimes here hair is on the front of her on one side, on the other side, and on both sides. This is the best way I can define it but if you see the movie you will completely understand what I am saying!