I have been having dark brown discharge/spotting and breast tenderness for 3 days now. i am 47. my period is due next week. there has been some tissue?

Anovulatory bleeding: At 47, you may be approaching the transition to menopause. This happens when the ovaries stop making the female hormones (estrogen/progesterone) and stop putting out eggs each month (ovulation). It doesn't happen all at once, though, and for most women, the cycles change gradually, which causes these irregular bleeding episodes (called anovulatory bleeding).