I am an avid animal person. Like a mini zoo keeper, or animal shelter owner. ;) I have always believed in spaying and neutering my pets, and pick up strays, take them to the vet, have them taken care of until I can find them a home.
Both of the dogs I have now... Samathia, my beautiful pure bred German Shepherd Dog, who is the love of my life - Though I paid nearly 2500.00 for her, was rescued from a Naughty Breeder. Being from a family who bred GSD's and Rotts, I was hoping to at least have my best girl breed at least once before having her spayed. YES, I KNOW. MY MISTAKE. Cody, my second dog a mix breed of Black Lab and something, he's a little love, was a rescue that I recently picked up that was injured. His insides were kicked in by previous owners, and could not hold his bladder. Poor little man. The thing with this whole conversation is...
I didn't know that he was old enough to breed, because he didn't "have" testicles. My Sammy went into season, which is nothing new to me. All of the other dogs we have are altered, and I was hoping to breed her with our neighbors GSD, who unfortunately was a male from her litter, I had found out in the interim. So I was hoping to get Sammy spayed as soon as I learned that I could not breed her with the neighbors dog.
Long story short, about a month later, she was making milk... Had breasts that were distended, and just became a huge momma's girl. She has never ever been an active dog, but now she is much less. I called the vet, who told me yes, she may be pregnant.
She told me everything to do, so I have been doing everything in my power to help her. Now she has no milk, I caught our Cody dog nursing off her, and think this may have caused a problem. She is only gaining weight in her rib area, and I can't tell if what I am feeling is a pup or not. Looks like I'm going to have to make the trip into town to see her vet, but does anyone have any experience with this issue? I'm sorry it is so long, but I just didn't want to seem like an irresponsible pet owner. I have no childre do to medical illness, but love my dogs with my life. I don't ever want to cause them pain. What am I doing wrong. Thanks All, and Blessed Be.

With all due respect you have answered yourself the dog needs a vet.
Also there may not be anyone on line right now who knows about dog's try not to be so impatient.

Sometimes things go bad for knowledgeable, well motivated people. The uterus branches back just inside the back legs. At over a month, the vet should be able to feel any puppies, with ultrasound and X-rays being even more reliable. Yes the vet for sure. Even if your mixed breed is neutered or undecended, he may have mated with her, which means no puppies, but perhaps an infection. It doesn't sound like anything that can't wait until Monday.