[Giada and Rocky]

My 10 month old 4lb yorkie went into heat for the 1st time on Halloween. I also have a 9 month old boy yorkie (10lbs). I tried my hardest to keep them apart (diapers and all), but i think they may have gotten to eachother. It is the 23rd day now. Her pee pee is still very swollen, and her nipples are more swollen then they were the whole time of her heat, and she is moody and sleepy. I dont really want to get her spayed right now. Are there any signs I should look for? And will she HAVE to have a C-section? I know she is very young, and I want to do what is best for her if she is pregnant. When can the vet tell if she is? Thank you so much for your help. They both mean the world to me and I really need advice... please be kind, I did not mean for this to happen...