Sore breasts are usually caused by elevated estrogen or progesterone, such as during pregnancy or PMS, but these things should not be happening with real anavar.
Most labs replace anavar with tbol or low dose dbol simply because the raw powders are much cheaper for them - its one of the most faked compounds on the market.
I noticed you said that the symptoms began this week, does this week also happen to be the time of the month for you?
Anecdotally, women do say that during their periods anavar tends to make the usual side effects worse - whether this is directly caused by var is another story (the evidence suggests it isn't, anecdotal reports say it is).
IMO, the women who report these stories & have excess water retention simply do NOT have real var. In fact, many women once they switch sources never report these symptoms gain - not a coincidence.