Thank you for your question. I appreciate your patience while I researched and typed out your answer.
Possibly. In order to prove medical negligence (medical malpractice) you need to prove 4 things:
1) The defendant owed you a duty (that's easy, a physician has as duty to a patient)
2) The defendant breached their duty
3) Causation - "But for" the breach of duty, you would not have been injured
4) Damages - you must have suffered some form of injury for the court to be able to compensate you. For example, did the misdiagnosis make the osteoarthritis worse? If so, they could be a form of damages. I know you mentioned having an anxiety disorder -stress, fear, depression, etc. over test results can all be forms of damages.
All that said, you'd want to talk to a personal injury lawyer in your area to determine if your case is worth bringing. Because these cases are most often taken on contingency, meaning you pay no fees unless the attorney recovers money, and because they are often very expensive to litigate, firms are very selective in the cases they take, so while you may have damages, if they are not considered significant, you may find firms will turn you down.
If you require additional information, press "REPLY" and I will be happy to assist you further.