you say you had the pain before the pregnancy so it isnt be caused by the baby but having her cramped inside there might be making it a little worse. I have no advice (never experienced that type of pain) just sympathy, the last few weeks of pregnancy are so hard and to add this other pain to it makes it harder. Im sorry
but just think soon you will have your precious little girl and you can also get to the doc and try to figure out what is causing the pain