I donate blood 3-4 times per year, before a donation hemoglobin will be around 16.5-17, Hematocrit around 48, after Donation they will drop to 15.5-16 and 46 but shoot right back up after next dosage of T, Ferritin will drop to 10-30ng/ml. I always feel like crap, attribute it to low Ferritin...