What I'm saying is that a lot of does will show a white mucous-y material that you will see at the end of the heat cycle- maybe even a few days after they have been bred. On my does sometimes I see it when it is white and wet, and sometimes I see it after it dries up and gets crusty. And, I'm assuming she was in heat when you bred her so the timing would be about right.
If you think it's something different maybe you could post a pic?