swelling along abdomen

Hi all i have an older red healer, she's 12, unfixed & never had puppies, really hates the vet and until last year she was the only dog in the family, after a friends sudden passing i addopted his pitbull pup and Calamity Jane, my healer, had a new brother, Blu, he has been a great dog but has brought some jealousy into the house , he was uncut when he first came home and as he grew it seemed to trigger her into a heat cycle, she had been getting beyond that, skipped several cycles. we had him fixed after he turned 1 yr old, since then Calamity has had several unusual heat cycles, and has now developed some swelling on her teats, the swollen area runs from teat to teat is about 5" long and soft, it doesn't cause her pain, she is eating and drinking normally, wants to run and play but i try to keep strenuous activity down, i don't want her to hurt herself and can afford vet care but i also know how traumatic the vet is for her. what advice could you share with me? thank you! :wave: