This really is tmi, but...
Did you feel much more aware of "down there" with the twin pregnancy?
Almost since my bfp (long before we discovered it was twins at 12 weeks), I have felt, well, like I had lots of sex the night before!
I am 99% sure I didn't have this feeling with DD until about 34 weeks... Or maybe I did, but not all the time like this.
Could it be the extra hormones with twins? Could it be a problem?