debilitated: your hgb would drop if you were cronically bleeding, have a diet that is deficient in iron or have a medical process that interfers with iron absorption.
Iron is a binding substance that ties protein and iron together to make the heme molecule, basic energy source for our cells (explains why your tired if you hgb is low). Iron deficiency anemia is the first indication of this issue, we are designed to hoard it (iron also carries oxygen and protect against infections). Iron absorption is done through ingesting animal proteins & supplements, occurs in the duodenum.
Common methods of iron depeletion: sweat, skin shedding, mucosal lining of the GI tract and menstral cycles, decreased with inflammation.
So maybe a long way to answer why you are feeling run down, fighting infections as well as slow fistual development slow wound healing). So keep taking those Iron supplements and don't be supprised if your doc wants to give you some medical assistance in this process. Improving iron stores takes a long time.
Sorry, this was probably more than you asked for . . am taking a mental break from work . . . and did I tell you its a sick world and this is what i do to relax . . .??