Looking for a serious answer to a serious question about my bunny?

My female silver marten (six months old) has small drops of blood in her cage. this is the second month it has occurred, and i've only noticed the blood for one or two days (not much at all, just a few), and then it stops. i know rabbits can have bad days, but when i have noticed the blood the few times it has happened, she always seems to be tired, but then the next day she's perfectly fine and bouncing around like she should be. this is a very idiotic question, which im pretty sure the answer to is no, but...do rabbits have menstrual cycles, and if not, what could this possibly be? i have a breeder friend i can ask, but i'd like several opinions from other people who actually know what they are talking about. this is my first rabbit, and im none too familiar with them, not like i should be. thank you.