RavenL,
I went for my first therapist visits in my life last January. It was nerve wracking for me as well. I had a hard time getting the right number, (the first therapist was through a staff support system) then had to wait till after the week end. I felt like shrinking into nothing. However, I was not where you are. I went to see what could be done to cure me of cross dressing or finding a way to cope, without my wife or anyone else finding out. So, it was a pretty humiliating start.
The experience was not easy. I do not like to talk about myself. You can see from my posts, my new self is better at that (maybe too good). However, I was very happy I had done it. After a referral to a long term therapist, it has helped me greatly.
As I said, I did not really know where I was in any of the trans spectrum. I did start to journal. I also found a series of essay style questions that help really nail down who I am. I almost think some of those could be used by the therapist in writing a letter and coming to approval of me as a MTF transgender person. The journal and questions things were not demanded of me by my therapist but she found them very helpful in the progress.
I could be wrong, but I don't think many therapists will sit and demand you prove yourself to them. They really are there for a number of reasons:
1) Help guide you through your own self discovery(you have done much of that already).
2) Make sure you don't head off down a path that is either self destructive or doesn't make sense as to where you are trying to arrive
3) To transition you will need some letters. I don't think they see themselves as gate keepers with a firm look waiting for you to press the right buttons.
I think they just want to see the real you. How you perceive yourself and if anything is hiding. I imagine you have little to worry about. I hope it is a lovely experience. It was difficult for me to originally say, "I have had a problem with cross dressing", out loud. Every time I spoke (and the sentence has changed) it becomes easier and tension seems to leave more of my life. It still comes back but I found these visits really help.
Others have mentioned before that sometimes you just don't click with this therapist. Unless you are in a small remote area, there are others to choose from(in that case, you might have to find creative solutions-they exist)/
Take a breath and give it a chance. If he makes you uncomfortable try to figure out if it is him or the subject. If it doesn't work, move on to another.
Wow, I try not to give overt advice. I try to suggest and give options. At the same time I think this is good advice. If it does not feel that way to you, please ignore it.
I hope you can get some sleep and go into this without too much anxiety or dread.
With loving thoughts,
Joanna