Well having a bitch miss twice
i think i know when she is pregnant and when not!! Boobs are a good sign but can also be indicators of a phantom, so id pay more attention to her tummy. At 5/6 she should definately be starting to show. if your still unsure at 6 weeks, i would recommend a scan as if you really are unsure and you will need to start preparing whelping box and all the kit etc. Which is more money! not a cheap venture. I wish it was 2-5 pounds!! last i paid was 47.50 allthough i prefer being in a rice warm room in the house with the whelping box, than a barn in february in the middle of the night, i was so close to the heater i nearly melted myself!!!