Pre term labor??

Hey girls! I’m currently 31 weeks and just moved to a new city where I had to get a new OB and whatnot. Anyways, during that appointment I was told that I’d be referred to a high risk pre term labor doctor just in case. Now, I have been feeling cramping, am originally overweight, and I do feel like my baby boy is sitting pretty low but I’m wondering if any one else has experienced pre term labor and what is your story?? How many weeks were you??did you have a gut feeling ahead of time that you’d be going into labor earlier than your due date?? Please share!!