The 2006 film featuring Magdalena as its central teenager is Quinceañera.
Magdalena is a Los Angeles teenager whose family is preparing for her fifteenth-birthday celebration. Her story becomes complicated when she reveals that she is pregnant, creating conflict with relatives and challenging expectations surrounding the event.
The film was made by Richard Glatzer and Wash Westmoreland, who wrote and directed it together. Rather than presenting a simple ceremonial story, the movie uses the quinceañera as the setting for a broader family drama involving faith, sexuality, housing, and belonging.
The title is sometimes mistaken for a documentary or for a generic label applied to several films. In this question, Quinceañera specifically means the 2006 independent feature film. The character Magdalena is fictional, so details of her experience are part of the screenplay and should not be treated as universal quinceañera practice.