Go in again and have him pull out all the fluid and show you how much is there. Better to play silly doubting woman on the ground than at 12,000 feet in the air. Also, once you are at the new appointment, after your fluid amount has been verified, then discuss with him what led you to need confirmation--face to face. If you don't feel comfortable with this then you could just ask his nurse to do the confirmation, but don't tell her why, just blame it on yourself saying you believe you misread the amount you saw the doctor remove and need to see it again for your own peace of mind