Hi, Welcome to JustAnswer. I am a licensed veterinarian and I'm here to help you. The swollen vulva of estrus is not usually painful, or achy, but can feel (probably does!) differently. Is your girl urinating and defecating normally and with normal frequency? Is her anus swollen or reddened at the site of the anal glands. . .4 o'clock and 8 o'clock. Can she move her tail normally?