Accidental dog fight~legal action question?

I had came back from swimming at the pool in our apt and mind you I'm juggling an uptight 11 month old and our dog and cat greeting us. We live in an apt complex and we have a door that doesn't always shut properly for some reason. There is a couple in our apartment who have a dog that whenever they walk it down stairs it barks and jumps up on our door. The one time I forget to latch the door because of all the distractions as I'm giving my baby a rinse off bath from the pool I hear barking from the dog upstairs and then our dog go beserk and the owner yelling "stop it" I run out there and our door is cracked open assuming that their dog had jumped on our door and both dogs started going at it. I didn't see it since I was in the bathroom with my baby. So I shut the door and proceed to get my baby dressed and then while I'm getting her dressed I hear a knock at the door...I screamed One Minuet and by the time I got to the door they were gone. So I went up to there apartment and knocked on their door to apologize for the incedent and they wouldn't answer yet I could hear blaring music so I'm figuring they were ignoring me. Could they do legal action against us? I mean our dog was just defending her territory and my baby and I...its a natural instinct when a threatning animal or person they don't know walks in our aptartment. I want to know what to expect because these people can be known for complaining a lot.