pump up the iron

i think i am iron deficient and am contemplating taking an iron supplement. i take a daily vitamin with iron in it, but i still have many of the symptoms of being low on iron. plus, i'm somewhat of a poster child of a person who would be anemic. i donate blood every 8 weeks (and many times my iron is boderline too low to donate), i exercise regularly, and i'm a woman. but, since too much iron can be very hard on your body i'm hesitant to grab a bottle and start popping pills. i've done much research, but would love to know if anyone has been down this road before. have you had experience taking iron supplements? non-pregnant experiences would be most helpful. i'd love to hear how it went!