As a child, I was bitten in the face by a white german shepard that lived across the street. Luckily this did nothing to change my love of dogs.
It breaks my heart to think this dog will likely be put down for the mistakes of humans. He/she was clearly telling you not to get too close and you didn't listen. Honestly, though, I would probably have done the same thing you did...and the owners are at fault for losing track of an insecure dog.