I feel you. I still have enjoyable sex, but my vagina hates me this time around every time afterwards it is swollen and sore. Plus that really thin piece of skin at the bottom of the opening bleeds every single time. So that makes it sting when I get up to pee after.
I don't really like sex unless I'm drunk anymore. Luckily for me, DH comes home never (work-related), so we have sex like...once a month, IF that. When we go long enough, I get sore. I think that's pretty normal.
Why don't you check with your doctor? Something should be happening to your vagina especially if you used to enjoy pregnant sex. You may have a little infection. When I was pregnant I used to have that problem after I had stopped having sex, so after a few days in a road it started decreasing.