I think you should just put a lid on the perfectionism and focus on performance without letting your feelings seep in but just going through the right motions. If you feel that you made a mistake, analyze why and see if it can be prevented. If not, then not. It sounds like the situation is already precarious for you job-security-wise because there can be severe consequences. The sooner you relax, the better. If you continue to be tense and perfectionist, it just might get you fired sooner or later. So beware.