Why did he supposedly have one? What’s your reasonings?
I can’t answer why he seemed to have an attitude. You’d have to ask him why he had one.
But complaining about every decision that went against and not doing much work – worthwhile or otherwise – in the time up to his first goal… those things suggest he was mardy.
Edited to add: I should say, for clarity, I really like Whitehall. He can just be an arse sometimes, and it looked that way for a while on Saturday.