Mini pill EBF and bleeding

Alexis • Mom to Eloise 👧, Iaen 👼, and Norah 🌈

I started taking the mini pill on Sunday at 5 weeks PP and noticed yesterday I started lightly bleeding. Could this be a side effect of the pill or a period? I'm EBF and didn't get a period with my first until I stopped breastfeeding. Has anyone else had this happen?