Anyone with normal MCV & RDW but low ferritin?

Hello,

I have had low ferritin for several years but my doctors have not been concerned. I found out I was anemic back in April 2008 but my MCV and RDW were in the normal range:

RBC: 3.40 (low)
Hgb: 10.5 (low)
Hct: 30.0 (low)
MCV: 88.2 (normal)
RDW: 13.1 (normal)
Ferritin: 6

My doctor called this "normocytic anemia" but attributed it to the low ferritin. After a few months of low dose iron supplements, by anemia had improved but my iron levels were still low:

RBC: 3.86 (low normal)
Hgb: 11.7 (low normal)
Hct: 34.2 (slightly low)
Total Iron: 39 (slightly low)
TIBC: 361 (normal)
Transf Sat: 11 (low)
Ferritin: 10

After another two months, the anemia had resolved and I was told to stop taking the iron:

RBC: 4.16
Hgb: 13.0
Hct: 38.47
Total Iron: 115
TIBC: 333
Tranf Sat: 35
Ferritin: 13

I'm wondering if I should have kept taking the iron because some recent bloodwork shows the anemia may be returning. I don't know my iron levels, but MCV & RDW are still normal:

RBC: 3.75 (slightly low)
Hgb: 12.2 (low normal)
Hct: 35.1 (low normal)
MCV: 93.6 (normal)
RDW: 12.7 (normal)

I was under the impression that iron deficiency produced "microcytic anemia" not "normocytic anemia". In iron deficiency anemia, I believe MCV is usually low and RDW is usually high. I'm not sure if my latest b/w categorizes me as anemic, but it's definitely normocytic and has always been normocytic even when I was truly anemic.

My question is, does anyone else here have normocytic anemia? Can low iron/low ferritin cause normocytic anemia? Perhaps my anemia wasn't severe enough to the point where MCV and RDW were altered?

Angela, 44
Still menstruating regularly
Possible mild Crohn's Disease