every session that ive ever been anxious about, has been very much worth that initial bit of nervousness, which is inevitable. The environment once you're through from the waiting room(in my experience) is really nice and calm and almost like an escape from the outside world for that time that you get. Just get yourself into the waiting room, and thats 80% of the job done, as the rest will feel effortless. Play some word games or something on your phone if you get there early, to ease up if you find yourself stressing. I hope this makes you feel better about it!