DeterminedSlacker, you absolutely did the right thing! BIG kudos to you for stopping to help that little girl. I don't like the word "shame" but I'm going to use it in this context: Shame, shame on that stupid woman for her lack of gratitude toward you. What a pity for that child to have such a mother. And here's my guess: I'd place bets that the woman was defensive about her child because she was embarrassed about not keeping a proper eye on her, and losing her in the store.

Don't feel bad for a moment - you were that little girl's hero today.