Remember when we told you that taming/bonding with a bird can often take WEEKS? That's WEEKS of gentle patience, bribes, and as little force as possible. Your relationship with your baby was already off to a rocky start with the toweling and gloves and grabbing. Now that he's been forcefully grabbed and manhandled by the vet you're basically back to square one.
It's also very common for birds to go through a "honeymoon" period when they first come home. Because they are still unsure or afraid of their environment they may be unusually docile or cooperative. Once they are more familiar with their new home and start feeling more confident they may go through a big behavioral shift. Instead of meekly going along with what you want they start asserting themselves with biting, running away, etc.
Now on top of all this your baby can no longer fly. I'm not going to judge your decision to get him clipped but losing the ability of flight CAN have significant effects on a bird's personality. Flight gives a bird the freedom of
choice. This in turn gives a bird an increase in self confidence. If a bird can't fly away to avoid an aversive situation it may resort to biting more instead (think of the "flight or fight" response). Which is one way that clipping a young bird to help with bonding/taming can backfire.
Again, I'm not trying to make you feel bad here! It's just important that you start looking at things from your 'tiel's point of view instead of only being concerned about getting him to do what you want. This is a relationship remember. You wouldn't go up to a girlfriend and tell her "Okay now you have to obey me in all things! You have to let me hold your hand whenever I want, you have to hang out with me whenever I want, etc". Instead you would ask "Okay what do you want to do? How about we do something fun together?" and give her the chance to say yes OR no.
Your 'tiel does not hate you. It is a common mistake when people start attributing human emotions to an animal's behavior. Doing so only clouds your vision to what is REALLY going on. So again, your 'tiel is not biting you because he hates you. He is biting because he's trying to
tell you something.
Right now he's trying to tell you that he is scared and does not yet trust you yet to touch him. So respect this! Start bribing him with treats and give him space when he shows you he is uncomfortable. In a perfect world a bird would have had no negative past experiences and so you might be able to get away with taming with frequent treats alone. But now that your bird has had a couple scary experiences you'll want to be even more concious about making all of your interactions as positive as possible.
It may take a few weeks (or even a few months) but remember you've got the next 2 decades to spend time with this bird! So let him tell you when he is ready to start being handled, or recieve scritches. Wishing you both the best of luck!
