Errors made by characters (possibly deliberate errors by the filmmakers): Ann says that her birthday is in December. Later, she says she is an Aquarius. The astrological signs associated with December are Sagittarius and Capricorn. An Aquarius would have been born in late January or early February.
Errors made by characters (possibly deliberate errors by the filmmakers): When Ann is talking about the conjoined twins, she says one was a girl and the other was a boy. Conjoined twins are formed from the same egg, so they are always the same gender.
Factual errors: Ann and Don claim they met at Nirvana's last concert. They live in Canada. Nirvana's last show was in Munich, Germany.
Continuity: Ann's fingernails after she gets them done.
Errors made by characters (possibly deliberate errors by the filmmakers): Lee says he's been to the desert in the south of Chile. Southern Chile is very cold and rainy. Northern Chile contains the driest desert in the world.
Continuity: In the scene where Lee and Ann are at Lee's house and Lee reads Ann a passage from a book, Ann throws away the book irritated after a few sentences. In the next shot, the floor where the book should have ended up is empty.
Continuity: When Deborah Harry is watching 'Mildred Pierce', we hear Ann Blyth's famous spiteful dialog on the stairway right before Joan Crawford slaps her. When we see the TV, we see a later scene, with Blyth in her nightclub dressing room.
Continuity: When Ann is standing in the rain at the beginning of the movie, she seems to be alone. In one shot, you can see a male face behind her.
Crew or equipment visible: When Ann and Lee are in the restaurant and Ann asks Lee to ask the waiter to put her food in a doggy bag, she stands up and the microphone in her back is seen