Unless you obviously messed up such as being unstable at DA and not performing a GA or worse you may only think it was bad when perhaps it was not. I had a job interview and after the sim they said so please debrief us on your performance. I replied "well firstly I apologise and secondly I would not employ myself off that performance" I continued to say what I did and how I could have done it better. I was told not to be hard on myself and that it was supposed to be difficult and they would be in touch. About a week later I was contacted and was told I had successfully passed the interview and sim. I guess it can't have been that bad then and I continue to be my own biggest critic.
Good luck