I just started on Levothyroxine 25 microgrames. My ferritin was a bit low 39.6 (20-291). So I bought ferrous fumarate 210mg and plan to take on each day until retest in 6 weeks. Does this sound good? Is it safe to start this on my own without talking to my doc? The pharmacist was a bit reluctant to sell it to me... Is there anything that I should think about regarding the tablets?