It is something to talk with the therapist about, but with the professor I am not so sure. I know that I have had a trigger recently that sent me into high anxiety and stress but because of my medications I take I would have no problem talking to a group of people unless the person I feared was in the audience. If you pin point the problem and read about how to overcome public speaking this can soothe over the situation with the professor to the point where you can assertively say you do have a form of PTSD or anxiety disorder and it doesn't interfere with your life anymore, meaning you have overcome the fear of the professor, because being evaluated for performance to me is not a reason to live in fear. I have lived in fear from phsyical abuse by angry conservative psychopaths which lurk everywhere and this is not fiction. In college I escaped this state to California, sometimes I cried to professors about topics of papers and I was never afraid of professors. They worked with me, and any professor would want a person that has a tick, a minor set back to succeed. But then again you can't be submissive about it, you must be assertive about the situation you are in to get the right advice and to lose the fear of being evaluated by an intrusive professor.