hi, i'm new to your forum but hope you will give me some advice about my girl, i mated her on day 11 and 13 of her season, mating went ok but with ties of just 3 mins and 5 mins , it is just 3 weeks since i mated her and she is eating very well and wanting walks, i have checked her nipples but the only ones that are showing any change are the ones nearest to her front legs and in the books it says the ones nearer the back legs show signs first, also she will not have anything to do with my other girl , they are sisters and have always loved each other and play all the time, i bred my first litter over 15 yrs ago and have forgotten what girls go through in their first few weeks , should i just ignore the fact that she don't want to play anymore with her sister , or still put them out together hoping that they will get on again,

Some bitches will not have anything to do with other bitches once mated and pregnant -that to me sounds like a pregnancy sign and if I was you I'd keep them separate to avoid fights. (A fight could of course result in the puppies being lost.) One of mine is like that, from the day she is mated until pups are about 5 weeks old she will not get on with any other bitch.
I wouldn't expect to see much change in teats until about 5 weeks.

The first physical sign is the nipples nearest her elbows...they have the most to change as they are almost invisible before conception. The large teats at the rear are usually the last to change significantly in my experience.

Hormones can change many behavioural traits.

I have had this with one of my bitches who from the moment we arrived home after her first mating ..she would not entertain her best friend a bitch of a similar age. She would not allow her in the living room until I put my foot down although we never left them alone together and they were fine when out walking.
On her second litter she was fine we didnt let them see each other until the following day after the mating then  allowed them together outside after than no boundary problems at all.

thank you for your replies, she is still not interested in her sister , only interested in food at the minute , fingers crossed she's taken