I would go straight to a vet. Years ago, I had a pom mix that had a weird mass under his skin near his chest. It turned out to be an air sac caused a punctured lung. There's no way for you to know what it is without having a vet check her out. Hoping it all goes well for you. Please let us know what you find out.
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Becky...mommy to Barney, Anna (RIP), Willie Jack, and Zoe... RIP Max |