I'm not so convinced you won't!
but in the case that you wanted to... you'd actually be below your baseline hematocrit (amount of red blood cells traveling through your blood vessels) level for a while. How blood doping works is along the same lines as donating blood. Take a unit of blood out, preserve it for a while, let your body replace the lost RBCs, then put the blood that was previously removed, and reinsert it into your body.
Truthfully, I have no idea how to actually perform blood doping but from what I understand, it takes quite a bit of skill and some decent equipment.
However... there are easier ways to increase your hematocrit rating such as finding ways to increase the level of the hormone erythropoietin which stimulates the production of RBCs.
In any case, it doesn't really matter, the body will self regulate to get the proper amount of RBCs it needs. Blood Doping is only temporary since the unneeded extra cells will die off without replacement, and i'm pretty sure erythropoietin stimulation curbs the body's natural ability to produce it.
Damn, I loved Anatomy and Physiology class...