[naniid]

You've articulated your problem well, and though that looks like a problem to you, in real life it is not, but you are too young to understand that. Questioning your ability is sign of desire to get better and that is more important than the ability to solve problems in a time box. Question yourself more, act on whatever you decide on. Intelligence follows.

Though I have lot of experience in IT, I go and attend the interviews which are way below my pay grade with no desire to join them from time to time. I fail most of them. I get insulted. They inspire me to learn more and I am old enough to understand that interviews are not true platforms of test of intelligence and I do not consider myself a super smart guy.

On the other hand, I interview a lot to hire software engineers into my team where I strongly believe my failures in those interviews had made me a better manager. I know what are the qualities I need to look for in people when I hire them.

I know failures hurt. You have to accept the pain and focus on learning from them.

Grab yourself a copy of 'Growth mindset'