As a younger woman, you are less susceptible to having too much iron. Instead of donating blood, you can simply monitor your intake closely and let nature take its course to reduce the iron in your system. Do check food labels - you would be surprised by both the amounts and variation in "fortification" in many products. For instance, Multigrain Cheerios have a
lot more iron than Honeynut. Also check any daily multivitamin you might take - many of these have 50-100% RDA iron... though the "silver" versions have none. And

reduce your intake of beef.
After almost 3 years of the low-iron regimen, I am finding improvement. However, I have started to have symptoms of mineral deficiency... apparently magnesium, manganese, zinc, and selenium... leading to leg cramps. I am now testing supplementing those while avoiding iron.