Constant Cramps

Since i woke up yesterday morning iv had this pressure in my pelvis like a dull ache when i sit still or lay down it feels worse just like the cramps you feel before your period starts im 26 weeks pregnant and I assumed it was just growing pains but im a little concerned that its not going away i tried drinking more water incase maybe i was a dehydrated but it didn't help has anyone had this? Should i be concerned? I think ill call my midwife tomorrow morning if its still hurting