As others have said, do not let this get you down at all. I was out of control on the lesson the hour before my test, I just fell apart. Me and my driving instructor had a break and a good chat, and I managed to calm myself down and passed my test with 3 minor errors. I only passed a month ago, and I love driving now, but I used to dread my lessons and try and think of every excuse not to go. I was a very nervous driver, i over thought everything. My driving instructor used to say that my driving was perfect when we were on the way back to my house and I knew where I was going without him giving me instructions, but as soon as he gave me an instruction I would crumble and do things in the wrong order, or try and do things too fast and mess them up. On my test, I probably sounded like a right weirdo but as soon as I got an instruction, I would repeat it and then talk myself through it, sometimes in my head and sometimes out loud.
To anyone else who is struggling with particular things, tell your instructor and ask for a lesson solely dedicated to that, I used to panic at roundabouts, so we spent a whole lesson doing roundabouts and how best to approach them. I also hated bay parking, weirdly driving forward into a space did not come easily to me, so we spent a whole lesson on that.