[Cha Cha]

I would at the very least take her in to have her examined for sure. My Moka had two heat cycles before I had her spayed. She was NEVER exposed to a male, but after each heat her nipples stayed enlarged. After her second heat was over, I took her in to have her spayed and my vet thought she was pregnant, even against my insisting she was not exposed, and I requested they continue with the spay. When they opened her up for the surgery they found she had closed pyometra. So, my point is that she could have something else going on to cause pregnancy like symptoms. At my vet's boarding facility, my dog is never allowed to interact with others. (Moka's spay no doubt could have saved her life had we waited until she was really really sick).