I have had my teil for about 3 months now and things were going great. He loved to come out of his cage and sit with me. He enjoyed lots of head rubs and was not aggressive towards me. He started flying and has gotten better but sometimes he used to miss and fall behind a chair or something (never getting hurt). I couldn't really have him step up so I had to physically pick him up. I've done that about six or seven times now. He's stopped missing when he lands but now he's sort of hand aggressive. When I go to take him out he hisses and nips but then steps up. Head rubs are out of the question and he's getting more and more aggressive. He's made me bleed on a few occasions... Have I done something wrong? I've never handled him roughly or treated him poorly but now he's been so mean. Is there something I can do to reverse this and get us back to how we were before?