Wolfin:
I am so sorry that happened to you. It really sucks. I can only imagine how you feel. I guess the boss kind of sideswiped you.

I really like Open Eyes suggestion to go meet with this person again, more prepared to address their concerns. You do not have to make excuses or defend your performance, necessarily. Just go in there and get more information about what they want changed and why they want it changed. Then maybe make a counter offer. For example, they seem to have an issue with your note taking, but you feel note taking is vitally important to remembering what you have learned. Perhaps you could explain that your personal learning style requires you to take notes. It is because of you dedication to the job that you take notes. It is also because of you dedication hat you want to fully understand what behavior needs to change and why, to make you more valuable to the company. Get the boss to open up to you more and see if you and he can come to an agreement on some reasonable goals to be accomplished by a certain time. Make sure the goal are very clearly defined. That way, you both know exactly what is expected and you can both clearly see when you succeed.
I guess I rambled on long enough. I hope you can use something from what I said.
(((HUGS Wolfin)))