Oh, that's bad. You didn't do anything wrong... I don't think. Did you click "Quit Quest" before or after you got to the place where you can rate the quest? If you clicked before that, you probably didn't complete the quest. If you rated the quest, you need to use "Contact Us" to explain your situation. They can see what's happening/has happened with your character, and if they see that you have indeed completed the quest, they can just put the pin in your inventory.