Should Lovenox Be Taken Post Total Knee Replacement?

I recently had a total knee replacement, feb. 8, in the hospital I received daily injections of lovenox, and I continue these injections at home. In the hospital they gave me an iron supplement to go with the injections, I was told to continue the iron at home. Every time I try to purchase iron in the pharmacy I"m told not to take it. Should I or shouldn't I? I get a different answer every time I ask a nurse, I will not see my doctor for another 5 weeks. I don't wish to become anemic. Could you shed some light on this please?