There are many causes for a low blood count - i.e. with your blood counts below normal. The causes would be dependent on your age. It can be from simple blood loss (most commonly from the GI tract) or from various blood disorders (anemias).
One test that can help would be an MCV (mean corpuscular volume) which should be included in the blood count. If low, it would suggest iron deficiency or thalassemia; if high, it would suggest b12 deficiency or alcohol use; if normal, it can suggest any chronic disease or blood loss.
Without more information, it is impossible for me to say what is causing it. In any case, this should be followed and repeated in 3 months to make sure that the blood count is stable.
Followup with your personal physician is essential.
This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.
Thanks,
Kevin, M.D.