Paris does a similar thing depending on tiredness and mood. I just let her cry till she's done, hold her if she wants and then she can tell me why she was upset and if we can or can't fix it, and if we can't why not. For Paris its always as a result of frustration. Just don't give in, cuddle her when she's ready and offer to talk about it. It can be frustrating and confusing but I actually prefer it to tantrums LOL!