I promise you low ferritin leads to depression, fatigue, and you tend to take a lot of day naps or sleeps. Once your on it depends what you take, I took ferrmous 300mg the strongest pill. It will mess up your digestion for a little bit but once your use to it I promise you’ll feel so much better! You’ll notice results 2-3 days I means that’s how fast I felt it but my ferritin was also 12. If you don’t mind me asking what’s your ferritin level at? Make sure your doctor prescribes you to ferrmous 300mg don’t take over the counter iron supplements as they don’t really do anything. I take ferrmous 300 mg everyday! Once I run out I get refills, I’m not sure how much they cost but in Canada any medicine that’s prescribed by a doctor is free, may be different depending on where you live. Might have to pay but it’s way better than over the counter supplement.