First of all, I do not understand who posted the original query here. On my screen, I can see Kanye Rogers posting the original query and later on a response, too. I guess it's a mix up due to some software problems.
I will consider that Shweta, who is preparing for CAT, is reading this. Shweta, please do not make any judgments about your own self from the results of CAT. And someone has mentioned about having "realistic expectations". I think you are quite realistic in expecting a good result in CAT. You need to dig deep and find out what your beliefs are.
Your goal is to clear CAT with good numbers and secure admission to MBA. You have to see if your decisions, actions, thoughts are working together to take you towards your goal or not! For example .... you are afraid of another bad result. This makes you feel nervous, you can not concentrate, your sleep quality has dropped down considerably.... and you lose time in worrying about what will happen if things go wrong. I hope you feel any or all of these are correct.
The real problem lies deeper. And at present, due to the limited information you have posted, and due to a lack of one to one conversation, only you are in a position to find out you "self defeating thoughts or beliefs".
Are you thinking ... "I must get into MBA, or it will mean that I am lesser than others, and life will be awful, and it will mean that I am not good enough" ? Please take your time and ask yourself questions like "what is the worst that can happen if I do not get into MBA" , or "what does it mean about me if I do not get into MBA?" and similar.
I hope you are able to read this. Please reply back if you wish to discuss this further. Once you are able to find out your self defeating thoughts, we can work on converting them into thoughts perfectly aligned to your Gaol of getting an MBA. We can discuss strategies and techniques for the same.
All the best.
Abhijeet Deshmukh, MD