You know, it could be nothing, but I would be getting checked out. I had a very similar situation, minus the period pain/cramping. But I had lots of lower back pain, my DS was posterior, and my waters broke and he was born at 35 weeks. He had also been head down and engaged for about 6 weeks. I know that doesn't necessarily mean anything, but obviously it can!

Having a prem is no walk in the park (although my DS was and is fine ), I'd be doing what you can to avoid it. Ring your Ob and ask for an appointment. Good luck!