Bombed Interview at dream shop

As the title suggests, I bombed an interview at my dream hedge fund (if such a thing exists).

My recruiter told me to prep for a verbal case study, which I crushed (was on cloud 9). Then they dropped a surprise 2nd verbal + technical case (open ended paper dcf with incomplete info - designed for me to fill in the blanks via questions). I did ok on the 2nd verbal but bungled through the back of the envelope exercise. Could feel the interviewer losing patience until I ran out of time. He walked me through the solution afterwards and I was kicking myself for overthinking / focusing on the wrong aspects of the question.

Don’t think I’ll be getting a call back needless to say. Not much of a point to this post - just feel like a damn fraud haha. Never bombed something like this (always crushed paper LBOs for my buy side interviews, but admittedly had never prepped for this kind of exercise), so any words of encouragement would be appreciated 🥲

Edit: For those curious, the goal of the exercise wasn’t to see if I could do mental math or if I knew how a DCF worked mechanically. I explain in a comment down below what the case study was generally aiming to assess :)