Mathematical Analysis is very hard

I've been working on my homework that I honestly should've started yesterday, but didn't because I slept all day. We've gotten to episoln-delta definition of derivatives and I'm struggling. It feel like everyone else in my cohort is doing so much better than me, and I've barely holding on. I've only been able to get half of the homework done tonight and it's due tomorrow evening so I'm hoping to do one or two more problems and that'll leave me with just a quarter. Unfortunately, I've already done all the easier problems and I'm a bit stuck on how to prove the rest of them. Grad school is not at all like undergrad. It feels impossible to know what to do to improve. I feel like the whole thing is a joke. Here's a bunch of stuff no one really actually understands, but we'll pretend we do and give you a bad grade if you don't pretend too.

TL;DR Grad school is hard and I'm very stupid