It might not be that you're a people pleaser. Could just be that, like me, you have a hard time asserting yourself. As though some how you'd be bothering them. But you wouldn't be. You deserved to have your $5 back. Or at least a second box.

If you were a people pleaser you would have intentionally bought more than one box or paid more than you needed to. But that wasn't the case. It was a mistake on her part that you never got your change back. I think you just didn't want to seem like you were bothering them, especially since she was a young girl. You were probably just being polite more than anything. Either way, you had every right to get your change back. But you shouldn't feel stupid about it.