I came to this lab to have my blood drawn .   You are in the right place . Roll up your left sleeve and have a seat .   What am I being tested for ?   Your doctor wants to know what your white blood cell count is .   What does my white blood cell count tell him ?   Usually if your white count is off , the doctor suspects an infection .   How much will it hurt ?   It is only a pin prick . I have to put this tourniquet on your arm to make the vein easier to find . 