Grammatically Correct

I was driving Parker to scouts last night, when I noticed a kid playing basketball in the street. It was dark.

"Watch it kid," I muttered, "You're going to get killed."

"What are you talking about?" Parker asked.

"Oh, there was a kid back there playing basketball in the street."

"Was? You mean you killed him?!?"

"No!"

"Then why did you say 'was'?"

"Because we've already passed him."

"I don't think you're using good grammar, mom."