Agree with @Gems_Bond
Your mindset is in spiders web - "surrounded by failures" (yes, you didn't know, you thought it's negligible thought) - there are many ways to bring you out of this, but the core ones would be - can I see positives in the past in that environment? (Because mindset/perspective is first thing for 0-1. Later, everything comes under 1-10
You're trying hard physically (writing exams etc..), this falls under 1-10. But without clarity on 0-1.
Try this - manifest +ve things about your surroundings for a week or two. You'll see the change in results (not drastic, but a positive one that converts you to have no fear, no matter what)
IISC is whole different level, you don't compare this with any exam in the country. Yet you appeared, just treat that as, "Hey there! I gave my best in IISC, I TRIED what many people feared, I guess, I'm ready for something tougher than IISC"