The jills vulva should go down within 14 days of being with the hob, but it's the act of mating that brings them out of season so not a definite marker as they could have not got pregnant and have a phantom pregnancy, The hair on her belly and legs will thin as she starts to nest around 3 week mark . It's sometimes hard to to tell if she's pregnant, they can be good at 'hiding' it ! just make sure she has a varied diet esp with calcium in it as they can go into calcium shock wich needs a vet pdq they are usually bang on 42 days after mating