Nana explained that the reason he got angry is because he had to play Lord Krishna's avatar and sing a little for his character.
He is not a good singer at all so his songs were recorded in Rashid Khan's voice. But when he reached the location, he was told that the songs got erased by mistake and that he would have to sing in place of Khan instead.
He tried to reason with Jha, but Jha wouldn't listen. He kept pressing on him to sing then and that they would dub it later. Nana lost his cool and admits to being very abusive and rude with Jha.
He hopes to make any compensation he can to recover the shooting losses but he cannot take his behaviour back. He is very upset that Jha was almost in tears because of the way Nana behaved.