AITAH for showing concern for a dog dangerously close to the highway.

A guy left his dog off-leash today with no collar or indicators of ownership. The dog was playing on the sidewalk, dangerously close to an extremely busy highway, almost entering traffic.

My partner and I pulled into the parking lot of the adjacent apartment complex to try and find the owner, assuming the dog had potentially gotten loose. We found a guy at least 100 yards away on a hill, smoking a cigarette. I asked him if he knew whose dog it was, and lo and behold, it was his. Instead of answering the question like a normal person, he proceeded to say the following:

"Why are people so fucking weird? Do you have any idea how many times people come and ask me if that’s my dog? Get the fuck out of here. You don't live here."

He didn't really answer my question.

First, it's an apartment complex, us being there for the under 2 minutes we were to ask a question did not warrant that type of response. Second, I feel his dog shouldn't have been off-leash, out of your sight, playing near a highway with no indicators of ownership.

He then told us he was watching us because "his kids are in there" (he pointed to his apartment).

This guy was not only endangering his pet but was also completely hostile and standoff-ish toward someone who seemed to be showing more concern for it than he did.

I might be misreading it though.

Am I the asshole?