Contractions at 31 weeks ?

I've had BH and these feel totally different. My OB told me BH are painless. I've been having spells of contractions for like 4 days now. I'm just curious if it's normal or if I should go to l&d to get checked. This is my first baby. They're really painful but I don't want to seem whiny so I haven't said anything to my OB. I called the on call doctor a few days ago but got no response. I would feel horrible if I was having preterm labor but I'd feel like such a wimp if it's nothing. 😞