I once called animal control when I saw a dog in a car, in a hot parking lot. This dog was barking and running around the car. I waited in my car's A/C for 5 minutes before calling, just to be sure I wasn't overreacting.

When I got through to animal control, I was told that the dog was not in distress. A dog in distress would retreat to a cooler spot of the car (near the passenger side floor) and not jump around barking.

That your dog was barking and moving around, it was not in distress.