Cockatiels get cranky as they get older. Audrey is no exception. He's very territorial, he only accepts affection when he's in the mood, and he dictates our schedule by screaming when he wants the lights off or out of his cage.
For the last several months, he'll get so angry that when he's sitting on your finger, he'll attack the finger violently and spread his wings out. If you don't distract him, he'll start flapping his wings and almost fall over. He gets so caught up in being angry.