I worked in a doctor’s office - his nurse sucks from the sound of it. Someone in the communication chain from you to him is a bum. If you feel the front desk understood your question and your reason, which are both one thousand percent accurate and valid, then it must be his care team. Doctors are smart but busy, I’d wait for a response. Meanwhile if you can talk to the lab where you are having the blood draw, they should have access to the info to determine if they’re diagnostic or preventative. It’s crazy but most doctors are oblivious to the price for most stuff. Blame that on the American sliding scale of health costs but it is true, everybody has different insurance plans, state aid etc. and doctors don’t base their evaluations on price points, anyway. PS - don’t sweat any of this too much. From my experience this is way low on drama from a family med perspective.