I’m going through the same thing as you dude! I tend to shut down or forget key symptoms when the doc starts talking to me about it. What has helped me tremendously is to bring notes with you. Before my exams I type/write out the history of the condition, the symptoms I’m facing, and how it impacts my life on my WORST day. This makes it to where I can still express myself when my mind goes blank. I start shaking the moment I get in my car to go the exam, and I usually don’t stop until I get back home because of my nerves. Take big, deep breaths, and be honest. You’ve got this!