There are 3 stages in total.
1st stage you will see he swell up in the vaginal area you may also see some bleeding or discharge. The male will be interested but she will not allow it or what breeders refer to as stand for him. 5-9 days
2nd stage swelling is still present some discharge light bleeding she will stand and allow the male to mate with her 5-9 days
3rd stage: swelling will start to diminish along with the discharge she will no longer stand for the male. 5-9 days