I found out last week that my one year old cat is pregnant. I found that her nipples had turned pink over the weekend so I took her to the my vet, they checked her and did an ultrasound and confirmed the pregnancy. My problem is that she never showed ANY signs of being in heat so I don't know how far along she is. She is starting to gain weight and i'm figuring she is around 5 weeks. When do they start showing?