Currently exclusively breastfeeding my 5 month old. my period has not returned yet, but today i had a little blood tinged discharge. whats this mean?

Breakthrough Bleed: Breastfeeding is similar to using a contraceptive that suppresses the lining of your uterus. Sometimes the suppression is imperfect and the scant lining that builds up w/out ever shedding, reaches a point where it does shed just a little bit and that can be the discharge. At 5 months with discharge, i wouldn't be using lactation as contraception. Consider an iud, implanon, or nuvaring!