Feeling guilty about not "doing well," well, then you have come to the right place.
First, you should redefine "doing well" to trying your best rather than just expecting all positive outcomes. “Doing well” is about working hard, not giving up and keep going when you face challenges. It is more about your will to pull yourself back up when you're at risk of a burnout, rather than being a perfectionist. If you did poorly on an exam, there is always another exam to do well in; as long as you are ready to learn and give it your best, then you shouldn't be feeling guilty at all.
Oh well, we all feel guilty at some point in time. It's just human nature; we are vulnerable to our psychological emotions. However, that isn't the way to tackle life. Life is all about survival, and it's completely normal to commit mistakes. And I believe that in this world, to be successful, you need to fall into pit holes, get up again and continue life with a grin.
