Help. Feeling Lost

Agree with other posts here, you have options so try to take a step back to appreciate that and allow yourself to feel confident about your position/trajectory. The implications for each path are very different given the broad aperture defined by this discussion, so I would emphasize the point made in one of the posts above and suggest that you take your time, research, and operate intentionally. Easier said than done given the constraints you articulated, obviously you were driven to post for a reason, but you'll get through this. Worse comes to worst, if your situation persists for much longer then try to get comfortable settling for middle-of-the-road effort/work product in the aspects of the job that are marginal enough to not put entire workstreams at risk yet impactful enough to contribute to the preservation of your sanity and mental health (small things add up here, i.e. if distributing notes from a call or MP then cut out the incremental 15-30 minutes of meticulous editing).

Also, and only you will know how applicable this is, but given the fact that the interaction with your VP seems to have been the trigger for your breakdown (understood that it was just the breaking point and not the only thing on your mind), I would suggest subtly shifting your mindset. Early in my career, I had the displeasure of working for individuals that were objectively infuriating in how they managed processes and allowed their stress to manifest in very unhelpful and emotionally charged ways. This is easier if you otherwise think your VP/manager has good intentions and simply struggles to regulate their emotions, but at one point I just realized that I shouldn't take unnecessary blowups or seemingly targeted and angry criticism personally, regardless of whether mitigating factors like positive intent exist. While there might be genuinely helpful feedback somewhere in there (often the case), the folks who act like that consistently are the ones with the problem. You learn to either take it in stride (if there's positive intent), or just tune out the annoying/hurtful stuff and not take it seriously. It's very rare that folks in that mold will be well-respected, as the negative personality quirks underlying your interactions will manifest elsewhere; your focus should be on those who both are competent and demonstrate a consistent dedication to professionalism/cordiality.

Outside of the above, I wanted to add my support. I also did my pre-MBA associate years at a MF, and it was taxing. I know it's extremely difficult to maintain perspective in the midst of overwhelmingly strenuous stretches. It's also very, very challenging to reconcile certain mental/emotional aspects of your situation; you likely derive an immense amount of pride/reassurance in the personal qualities you attribute to your success thus far, but in the really tough times you begin to interpret each setback as evidence that contradicts the narrative you've established about yourself. That cognitive dissonance compounds in a very toxic way, which at best is discouraging.

I've been where you are mentally, so allow me to share with you the words that gave me license to open my eyes and begin to turn things around: while you may be questioning a lot of things, in particular the story you've been telling yourself about the path to your current situation, you should know that the emerging narrative underlying your self-doubt is the actual lie here homie. Two things can be true at the same time: your success isn't a coincidence - options were open to you for a reason - yet the specific situation you find yourself in might not be right for you and/or has likely been influenced by factors outside of your control.