About 3 or 4 days ago I noticed some tenderness in my right breast (not the nipple). Im due to get my period in 2 days but this has never been a symptom of mine. I was wondering if this is normal. Im 20, there's no soreness anywhere else, no discoloration, and I really don't think I'm pregnant. Ive just never heard of only one breast being sore before menstruation.