Bleeding between periods

Does anyone else bleed every time they do cardio? I’m trying to get into shape and stay healthy but every time I do cardio, I bleed even though I’m not on my period. I’m already on a medication for my heavy periods because I’m severely anemic and need to reduce my bleeding as much as possible. I don’t even attempt strenuous exercise while I’m on my period because it makes it worse. And I bleed during ovulation. And now this breakthrough bleeding is really annoying! I’m just trying to stay healthy dammit!