DD is 6 months old and recently (within the last week) sometimes when she is nursing she is clamping/pinching down. It hurts!! Why is this happening now? I have never nursed this long before (I pumped with my son) so is she getting teeth? Is she trying to get more milk? Whats going on? Its not excruciating so I can live with it but I really dont like it either, it does hurt. I use a shield too