sounds like Symphysis Pubis Dysfunction - this is what i have and i am in agony 24/7. i see a physio through the hossy and i wear a belt that prevents movement in my pelvis area.
i am often up to 2 in the morning (and on huggies to help pass time) cos i cant sleep bcos of the pain, even though i soooo tired. and once i am in bed, i cant move, dh has to literally roll me over if i want to me. and just recently i can no longer drive as my legs feel so heavy and i cant phyically lift my foot off the accelerator and onto the brake - it is very hard to explain (try lying on your back and lift one leg up - i haven't been able to do t his since 24w, it's like my leg is gead weight and i just cant get it off the bed - physio got me to try)