I have a 3 year old female cockatiel who is really sweet but recently shes been acting defiant. For example shes potty trained to fly to her cage to poop and then she flys back to me but for the past two days shes been flying to poop on me then flying back to her cage. Another example is she only wants to be touched when she feels like it,and if you dont pet her she hisses and angry nibbles me. Also when shes with my other birds she acts like she doesn't know me and hisses at me. Do birds have teenage years or is a seasonal thing?