I think you have typical pre-session jitters but you have the added anxiety of a new T AND an 'expert'. I'm not denigrating that new T will be very good but I think we may sometimes give extra wisdom or power to those we deem more qualified.

If this new T is as good as your old T says, she will be very aware of your fears and will never minimize the trauma you went through. She will be gentle and caring and understanding and compassionate. She would never belittle you.

And remember, the T who 'just totally seems to get your issues', is the one who is referring you to the new T. Trust her!!!