My white blood cells are low, but i never get sick. is this normal?

It depends: We need the complete blood profile with total white blood count, and differentials, like nutrophils, lymphocyte and others. Low white count can be due to recent viral illness, other causes are certain meds few other conditions but to answer your question, we need more information you should check with your doctor or a hematologist as you may need further testing if the doctors if it is significant.