You probably do not have a case:1) Even if there was malpractice (see below), there must be some damage or injury--other than just being upset; the law does not provide compensationo for that--resulting from the action. You would not have suffered physical injury, so unless you can show that you incurred some significant economic loss or cost due to the incorrect diagnosis, there is nothign to sue for.2) Even if there was injury or loss, the mere fact that the doctor was wrong does *not* mean it was malpractice. The law accepts that sometimes the best doctors do everything right but still get it wrong--the practice of medicine is not perfect. You would have to show that the doctor, in administering, analyzing, and/or reporting the test results, did not provide the generally accepted level of medical care--i.e. that he/she was careless, poorly trained or educated, using the wrong techniques, etc.--to establish liability.