I think he is upset because of my past perfect progressive correction;
He said: you be drawing. You always want to correct somebody or make us correct you…
I said: I always practice in this way. Therefore, I had been drawing, but if it was exclusive to you, then you really could say that I have been drawing, but it's not so rest assure, and know that if we try this again tomorrow and I exclude the rules for everyone except you, then I will have been drawing.
He really liked that!