welcome to HCM!
A bloody discharge from the nipple may be alarming, but in most cases it is
caused by a benign condition however it is a reason for concern and more testing.
If the discharge is coming from more than one breast duct or from both breasts it is often from a benign condition such as fibrocystic changes or duct ectasia .If the discharge is from a single duct, it can be caused by a
benign condition like intraductal papilloma
or duct ectasia.
since there is tenderness there can be infected hematoma
.get yourself examined.take care!