I had blood taken from my elbow after my daughter was born, it was very painful and left a large bruise, even the Doctor's hands, where he was gripping me hard so the elbow didn't move, left bruises. If it's the same sort of blood test that I had you are lucky it was done while you were under, it's very painful. The doctor was very apologetic but needed to get blood from a deep protected vein, because veins close to the surface would be saturated with whatever was in the IVs. He said it had to be taken at a joint deep between the bones.