Coach's bizarre complaint

[cgb2010]

In a 6th grade boys game, A is down with about 30 seconds left and calls timeout after they make a basket to cut it to 4. During the timeout, as I have consistently said to coaches for this age group, I tell the coach that I'm aware his team will be trying to foul, and to make sure the fouls are not excessively hard. Sure enough, on B's inbound, B1 ends up with the ball after he decks A1 while going for the steal. Free throws hit, game ends after one more possession. After the game, the coach said my comment was inappropriate, and it showed I was changing the way I was officiating because he didn't think that there was a foul on the steal.

I've never had anyone take issue with this, but I felt like this guy was challenging my integrity and if it weren't the end of the season there probably would have been an issue. I'm just hung up on it because this is the first time I've been directly confronted after a game like this (my experience is 6 years at this level + 3 years of college intramurals, I started with this league out of high school). Any tips on how I can handle something like this?