My guinea pig Gilli (6 years old) has been recovering from a raging UTI with Baytril and has been doing wonderfully, gaining weight and energy. Now suddenly overnight one breast became swollen and large. When I gently pinched it, she showed no pain but a little bit of clear liquid came out. Is this a side effect of the Baytril or UTI? Is she in heat? There's no boy guinea pigs in the house, so she's definitely not pregnant... Please help if you can, I'm so worried!!! It is not red or hot or discolored, just round and squishy, I did not feel any lumps.