Low WBC count, Low serum Iron, Dizziness, Anemia or leukemia ?

I am a 39 year old female and a vegetarian since I was 7 years old. I have regular check ups and have never before had an issue with my iron; however recently I have been extremely tired and unable to concentrate. My blood work showed a low white blood cell count at 3.0, Hemoglobin low at 9.5, Hematocrit low at 31, MCV low at 71, MCH low at 21.7, MCHC low at 30.6 and my RDW high at 15.3. My red blood cell count was within the normal range. It also came back with my Serum Iron low at 19 (with a normal range of 50 to 212) and Ferritin low at 2 (with a normal range of 10 to 291). I was told to take a daily iron supplement and come back in in 3 months to have my blood re-tested. Two weeks into taking the iron supplements , I still feel absolutely awful, even perhaps worse. In fact, I fell down several stairs on Friday from a dizzy spell. I now have a productive cough, nausea when I exercise and shakiness. I am concerned that perhaps I should see a hematologist to rule out more serious causes for the anemia, such as leukemia or other disease, rather than wait the 3 months to be re-tested. My questions are as follows: Is a low white blood cell count common with anemia? Should I see a hematologist now go review the results or wait the 3 months to be re-tested by my primary care doctor? Would it ever be recommended to have iron shots or IV for someone with my iron levels? At what point does iron deficiency call for a blood transfusion? Thank you for your help in sorting this out. - Melissa