I've been learning for nearly a year, two lessons a week, and I am still ages away from being ready to take my test, so the OP here is way, way ahead of me. If you feel ready, if your instructor thinks you are ready, you will pass eventually. My NT sister took four goes to pass her practical test... there are so many things that can make you fail, it was something different every time for her - it wasn't as though there was one or two things that were catching her out.
There is good advice here, to not have any expectations. Be confident in yourself though, are you safe to be out on the roads by yourself? Can you get through fast, busy junctions without causing problems for other road users? If the answer is yes, you are much better off than me. Try to see the test not as a test as such, but as an opportunity to show them that you are a capable and confident driver.
Nerves are a nightmare, anxiety will take you over in situations like this. Now you know the issues that you will face, maybe you can look at some relaxation techniques or therapies that could help you get a hold of those nerves. If you have a diagnosis, letting them know might not be a bad thing. In these "enlightened" times, see what accomodations they can make - being public officials I'm sure they will have been on diversity training weekends or whatever. And if they haven't or they ignore your needs, grass them to the local newspaper
I plan to be so good at driving that my test is going to be a cakewalk. My instructor says my lessons are harder than the test will be... I hope this is true, cos at the moment, the lessons involving roundabouts and dual carriage ways are freaking me out. It may take me another year, it may take me two. I might pass first time, I might pass on the fifth. I am trying to be very chilled and calm about it.