Hi I Am 40+6 Weeks Pregnant And For The Past

Hi i am 40+6 weeks pregnant and for the past hour or so every few minutes ive been getting a pain travelling up the lefy hand side of my back to my shoulder blade and then it stops i also have tightening in my belly every few minutes but it doesnt seem to be painfull could you tell me what this means? Also baby is in back to back position