What is the significance of a bloody discharge from my nipple?
In the non-pregnancy state, a bloody discharge can be a sign of breast cancer, and it would be very worrisome; however, in pregnancy there are often mastitis (inflammation) changes in the breasts, especially when there is the engorgement that accompanies milk "let down." Anything inflamed can bleed a little, be it sinuses, zits, or any number of things.
The fear of cancer is lessened considerably, then, when you're pregnant, and most likely represents a harmless problem. But...it's not a guarantee, of course. You need to talk to your health care provider just to be sure.