Stopping my reversed car with hand on brake

I was in a full parking lot and I left my suburban idling in order to fetch my two-year old who escaped the arms of my twelve-year old.  And I guess I had my car in reverse because I watched it going backwards. Well I decided to be a great sprinter and luckily I left the door open. Anyhow, my car missed hitting people and cars.  And I stopped it a half an inch before hitting the firehydrant.