Luna, I went back and read your whole topic
To help me under stand and help you better could you answer a few questions?
What was the day you brought Mona home from the place she was, with the 13 hh stallion?
Was she ever in an area with your stallion? If so what dates?
When was the last date NayNay was with your stallion?
I ask because wee foal 120 are usually correct, even if slightly contaminated, However I wonder if your stallion somehow got with Mona and perhaps she is starting some development from a fling with him
I had a shetland mare named Bonny ( my user name) Who * came to me bred, but wasnt, during the time I thought she was bred from the place she came from, she started to develop an udder ( looked exactly l;ike your mares) However I had brought in a mini stallion to breed a different mare and he covered Bonny. She carried that same udder for almost the entire pregnancy and was not bred when she came but was bred from the mini stallion I brought home. So I ended up watching her for almost a YEAR! It was my first pregnant mare, my first experience and Boy was I thankful to have friends and ppl here that helped me.
Being that your mare has had many foals, and negative 120 wee foal) this could be early pregnancy hormones changing, or could just coincide with heat cycles. After looking at her side view pics and the front view pics I dont think she looks like a mare due to foal anytime soon. I would be suspect that she may have had a night out with your handsome fella!
With all that said, lol, Heres what I would do, try and find a Vet that would be willing to Ultra sound her, or have a blood pregnancy test done. You could also wait til spring, wee foal 120 again and start teasing her to your stallion, all the mean while checking her udder.
I dont want to see you go through what I did, it was very exhausting! I wish you all the best and keep the pictures coming. I know the Ladies here wont mind helping answer any questions you have. And I sure hope you get to the bottom of this mystery!
Ladies, what are yalls thoughts? I certainly dont want to leave out yalls opinions!