Ohhh at 38 weeks yang sakit pinggng memang sangat common lah, especially with third baby because ligaments dah stretched from sebelumnya, but macam yang you describe, sakit sampai nak nanges bila bergerak itu boleh jadi pressure from baby position or something else, so better you check dengan doctor ke midwife kau yang handle just to be sure je. A few of us pregnant mums experienced quite a bit of ligament pain towards the end, tapi kalau dia really affecting your daily movement and causing that much distress, don't wait lah, tak ada susah pun tanya, they can give you proper relief or confirm everything is fine, at least your mind will rest.