I was diagnosed with severe anemia last year after having a bad reaction to some antibiotics and months of neglecting the symptoms. I received a blood transfusion and have felt much better. However, from my recent blood test, my ferritin level seems extremely low: 4ng/mL; reference range 10-154 ng/mL. Prior to the blood transfusion, my ferritin level was within range (12ng/mL) but has progressively decreased afterward. Everything else is normal, though - iron count, number of blood cells and hemoglobin, etc. My doctor told me not to worry about the ferritin, but it's puzzling why it has dropped so much. Should I be worried? My health is great at this moment and I no longer feel the anemic symptoms (although I do feel tired at times but that can be blamed on my poor sleeping habits). I'm also not taking any supplements and I'm pretty sure no one in my family has celiac sprue, or any disease related to iron level. Anyone know the answer to this mystery?