As Yogababy said, this is very normal. You'll also find this is often related to developmental milestones too. The wriggling sounds like a new skill that she is practicising and this interferes with their sleep. I don't want to be the bearer of bad news, but you'll go through these stages for things like sitting, crawling and standing milestones. But the good news is that since she was such a good sleeper before, she will more than likely go back to being a good sleeper when the stage passes.