My 12 week old puppy got upset with me for trying to pick her up and was growling and trying to bite me. She only made one tooth mark but I'm wondering if this means she will be too aggressive when she's bigger. She had been playing with another puppy but started to get too aggressive and the other dog was trying to get away from her. I held her by her collar and tried to lead her to the porch where her leash was. She was still trying to get to the other dog so i picked her up and she got very angry. She was trying bite my hands. She has played with other dogs only two other times and we didn't have a problem. I'm not sure why she got out of hand this time. I'm just hoping she isn't always going to try to bite when shes upset because I have a 7 year old.