27F, regular menstrual cycles, no medical conditions, I don’t take any drugs (not on hormonal birth control). Had strep throat two weeks ago. I’ve been having protected sex. I always use condoms correctly and I don’t remember any of them failing. Around my 15th cycle day (February 12nd) I got really sore nipples and that’s not a common ovulation symptom for me. On the 20th cycle day (February 17th) I started getting sore, swollen breasts. I found that weird because I usually get that as a PMS symptom only around 25th CD. I wasn’t scared of pregnancy because I use condoms but I took a pregnancy test anyway and it was negative. Got my period on February 26th as expected (28 days cycle), 3 days after the negative pregnancy test. Normal flow, bright red blood as always. Now my period is gone but my right breast still feels swollen and sore when that symptom usually goes away on my first~third period day. I don’t feel any lump when I touch it, no skin abnormality. Just feels like “PMS boob”. I’ve been having nausea and mood swings, too. Never had this before. Could this be caused by hormonal imbalance? Should I be worried?