Tips for talking to a coach?

I worked a game tonight. I called a foul on team A, and reported it. As I settled into my trail position, an assistant coach of team B asked, "are you going to call that on both ends?? It's happening to us too!!" I calmly responded "I hear you coach." Later in the game, during a timeout, the same assistant came up to me and said "You said you were going to call [that foul] both ways, but you are not. Why not?" I told then man, "Coach, I said 'I hear you', not 'I will call it on both end'". He clearly misconstrued my acknowledgement of his thoughts as an agreement for me to give his team a call on the other end.

I feel that my saying "I hear you coach" is a good, standard answer to give a coach when he says something like that. I have heard from veterans that you don't have to agree, but allow to coach to express his opinion and then acknowledge what he said.

Is my thinking wrong? Should I have simply ignored the coach the first time? How can I say things better so the coach does not think that I have agreed to give him a call?