Heavy periods

I’ve been having a down trend of my ferritin so I wanted to get ahold of my flow . I also have gut motility issues.. I took one dose of a low combined birth control and my gut isn’t happy and didn’t sleep well. I don’t really want to continue it after one dose.

Does anyone have suggestions? I have fatigue crashes every cycle for 2 weeks almost . The ferritin and prostoglandin is a problem . I’m wanting low clot risk too … iud seems good option but scared me .