Sure, the kid is not having all that great a day. But she also doesn't seem to have any idea about how to improve things for herself. Blow off a younger sibling who just wants some companionship? Go to a mall and sit in an empty food court? Kick over a display and run like hell? Steal a CD from a store and try to hawk it? Find no joy in the inane 'happy birthday' recording in the card? Sit moodily while showing no interest in eating your birthday cake?
Teenage angst is a very real issue, and this film captures it quite well. But it does not show who and why the protagonist was left so alone, and certainly does not even come close to pointing to a direction out of her troubles.
A description, not an interprteation let alone an analysis or a solution.
