I am sorry to hear this. I think it is important not to demonize his behavior.
One never knows what is going through a birds mind so there is really no point in guessing. Whatever it is that he is thinking he actions seem to indicated that he doesn't want you to be by him right now, again, I don't pretend to know why. Bird's don't generally bite if they want you to stick around.
I would give him more time and keep him at a safe distance until he calms down.
With biting, there is always a reason though it may not be apparent to us. You do not want to reinforce it or set a pattern, I know you would never do anything scary or mean in response to a bite. On the other hand, there is nothing positive to be done either (you don't want to reinforce the behavior by following it with something your bird likes or wants), unfortunately just quietly stepping away or leaving might be exactly what he is trying to get you to do so every time he bites you may be inadvertently reinforcing it. Reinforced behaviors increase with each incident so the very best thing to do is AVOID THE BITE. Sorry for the caps but it's that important
Whatever you need to do to avoid getting bit in the short term is what you need to do. Have someone else in the family take care of him if needed. Whatever has changed (even if only in his mind) may take some time to adjust too. Watch his body language, if it is saying back off then step back, not forward. Let him know that you understand what he means and that he doesn't have to bite to show you. If all indications look safe then you can offer a treat, maybe put it in a dish or use tweezers. It may be possible to hold it in such away that he can only reach the treat and not your fingers from inside the cage.
I know it hurts. Basically, my advice is to start over in building trust as if his actions today where his actions from day one. Try to win him over. Any negative reactions are a setback and the quickest way to win him back is slow and cautious, take nothing for granted, pushing will make it take longer. As he mellows and his body language says come closer then do so with caution.
I hope all this makes sense and most of all I hope it is helpful.