Slightly concerned, 35 weeks.

Jessica
I have had on and off period pains today. Started once I woke up, at 8am, nearly 12 hours later they're still there and my pelvis hurts. 
Baby's 3/5 engaged so low down. First baby however. I just feel slightly concerned. I've rested all day, drank loads of water. And they're still there. I rang delivery this morning and she told me they were BH. But surely they don't last all day?! Thanks ladies.