I totally understand that worry because after my second child, my cycle was all over the place for a good few months and I kept second-guessing every little thing I saw. My body took a while to settle back into a rhythm, and the irregular spotting and discharge really stressed me out until my gynae reassured me that postpartum hormones can cause things to be unpredictable for some time. That said, since you have been noticing blood mixed in with discharge on and off over a few weeks, it would be a good idea to pop by and see your gynae or PD just to rule out anything like an infection or retained tissue, because it is always better to get it checked than to wonder. You are not alone in this, and many of us have gone through those confusing postpartum months where nothing feels quite normal yet. Take care of yourself and I hope you get some answers and peace of mind soon.