I watched the game on TV and also didn't see Amauri being angry at Trez. It's reasonable he was disapointed because the ball went to Trez instead of him, he needs the goals even more than Trez. It did look "ugly" when he didn't ran after Trez immediately, but Amauri is just bitter at himself, not Trez.
But my suspicion, like you, is more that he's frustrated with himself. That's actually not too much better, IMO. We cannot afford to have a player who is grading himself so intently on his own performance to the point that he totally neglects to recognize the successes of the broader team around him.
As such, it's still a form of very selfish play. If Amauri cannot shift his own attention to his teammates instead of himself, it may be a while before I think he's ready to start in a key match.
