I have exactly the same problem, so it's also very hard for me to talk and express myself freely. Earlier this year, when I got tired of this, I started taking pills before my session but it was worse because I was so tired I counldn't even stay focused, so I stoped. I talked to my therapist about this anxiety, and trying to take it away, and he said it would actually be better to focus on it and see where it's from. He said anxiety was caused by all of those things that want to get out except I try to keep them in. Does that make sense ?

So I think you should do that too : try to see what's causing this anxiety, accepting it, and see what happens...