She will be in heat for 3 weeks, just like all other Unspayed canine females! One week going in, one week in and one week coming out! Keep her away from all Unfixed males and if you have a male in your home, you need to separate him from your female for about 3 1/2 weeks, just to be safe. He will do whatever he has to, to get to her, mate with her and get her pregnant. When you talk to your vet, ask when would be a safe time to have your female Spayed. You won't have to worry about her going into heat anymore, you won't have to worry about her becoming pregnant and getting her Spayed, will eliminate the chance of her getting certain types of Cancer. She will be happier and healthier in the long run!