Welcome! I am Dr. Altman, a licensed veterinarian and happy to answer your questions today.
There unfortunately is a possibility of her being pregnant but she can also be going through what is called a "false" pregnancy or pseudocyesis. Dogs going through this can go through every stage of pregnancy and even act as if they are going to whelp with nesting and milk production!
So my recommendation would be to have a veterinary exam. You can have an ultrasound done at this point to ensure she is not pregnant (can be done after about 24 days of pregnancy) or you can wait until she is 45+ days past her heat to have an x-ray done (when puppy bones
mineralize and show up on x-rays).
Once you have this information it will help guide on how best to move forward with her, whether a diet supplement is warranted if she is pregnant or if it is a false pregnancy
waiting it out (there is no treatment for this, even spayed dogs can sometimes show this sign).
I hope this information makes sense but please let me know if I can assist with any additional questions or concerns today.
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