[suninthesummer]

Hi All,
Sorry to start a new thread because it is similar to the snapping one below but a bit different as to when she does it.
My little girl is one and some of us have started up a yorkie club here in New Zealand. We went for a walk yesterday and Ella was so badly behaved, I was so embarrassed.
She is very submissive to bigger dogs and will immediately flop down or roll on her back but the dogs who were smaller than her she was very aggressive towards and would continue being aggressive when she was picked up or taken away and she nipped a few hands during her tantrum. (Not too hard but a bite none the less) I was so shocked because I have seen her be grumpy to our cat or rabbit around food or for grooming but not to the extent she was with these other dogs around. She would get up on my lap and growl at any dog that came near. Even if I was holding her and we stood near another dog she would perform. I just grabbed her and took her away from the situation for a bit. She did settle and was playing after a while but was still aggressive at times.
I realise I really need to address this behaviour because I know it is not right but I'm just not sure how. I have been advised to use time out when she growls and am trying that now, it is difficult when we are out though.
I was also told by her breeder to flip her on to her back and pin her down because that is what other dogs would do. I can't do that with other dogs around and I am thinking it might be making her more aggressive.
I know she can be a bit of a princess so I am also trying not to give her too much attention.
She is my first dog and I am trying my best but I really need help with this. I absolutely love her to pieces and I love going to these outings but if she continues to behave like this I won't be able to take her. Apart from this she is a great little dog.
Do you think it is a dominance issue or is she scared and being protective? What should I do?
Help please!! Any advice would be greatly appreciated.