delivered on the 19th and I had wicked hip pain during labor because baby was turned slightly to the side in my hoo hah. Afterwards it was more my tailbone and my in-betweenie that hurt.
I imagine giving birth does shift things around down there a bit. If your doctor is letting you use motrin, go ahead and try that. I used a heating pad for a few days and that was really soothing too. Maybe also try putting a pillow in between your bum and whatever you're sitting on to help distribute the pressure a bit more?
I delivered on the 17th too I don't have hip pain like you're describing but i get some intense pain in my back where the epidural was put in