I agree with Suse, I'd go get checked sooner. I had weeks of pain and discomfort prior to having DD2, I had period type pains on/off for hours. I also had heaps of movements even up to the day she was born! My pre-labour started around 36 weeks and she came at EDD + 13 days! So it may just be your body leading up to it, but having said that, its best to get checked out as soon as you can in case your bub wants to come sooner!