Don't beat yourself up, everyone can have a bad day (remember mock exams, dress rehearsals etc). Suppose that your glide approaches had been real forced landings with no power. In two of them (the touch and goes) you would have landed, even if the rollout had gone wrong. In your long landing, you would have been down, and it is proverbially better to crash into the upwind hedge whilst decelerating than to stall and spin into the undershoot. Imagining this to be a real emergency, you might be looking at: aircraft broken, crew alive, which counts as a success. Presumaby your go arounds were caused by being too low on the approach. If too high, maybe try a session on side slipping. Overall, if your instructor says you are ready for the test, he/sahe is probably right. Good luck.