Lumpy Nipples

Question
Hello, I writing to ask you about my cats nipples -- they have recently become swollen and firm and there's about a 0.05% chance that she's been in contact with a male cat.  She appears to be going into heat right now and I'm wondering if it has anything to do with that.

Also, we recently introduced a jack russel puppy into her domain and she appears to be under a little stress because of this.  For a few days she was vomiting in almost a territorial manner -- on our bed where she sleeps and the rug outside the bedroom.

Should we be concerned about this?  

Answer
Hi Travis.  Swollen, firm nipples are definitely a symptom of a heat cycle.  Unspayed females, after their first heat cycle, can be in heat for as long and as often as they want.  You may want to get her spayed.  Spaying a female cat will reduce her chances of mammary tumors and cancer and uteran cancer by 99%, and completely eliminate the chances of her developing a severe and often times deadly uteran infection called a Pyometra.
It definitely sounds as though she is stressed and territorial over the dog's appearance.  If this is the case, she should be over it in a few days.
If you are noticing a green or unnatural vaginal discharge accompanied with the vomiting and swollen nipples, she may be suffering from a Pyometra.  Other symptoms are lethargy, decreased appetite and painful abdominal area.  If you feel as though she is displaying any of these symptoms, getting her to a veterinarian asap is crucial.
Please let me know how it goes!
Hilary