36 weeks and feeling sore in lower abdomen...

I am 36 weeks 2 days. I work in an office, so a good part of my day is spent sitting down (aside from my gazillions of pee breaks!) - anyway, yesterday and today when I stand up after sitting for a while I am feeling lots of pressure in my lower adbomen. I feel very sore, again, in the lower abdomen... and its even hard to stand up completely straight. After walking for a bit it becomes less painful, but it doesnt go away. It is completely relieved when I sit down. Does this mean the baby has dropped? Do I have this to look forward to until she is born?? Just wondering if you other ladies have felt this way. It sucks!