"I did everything right."
fwiw, this is a huge red flag.
the first thing is, it's p notable that not a lot of people claim "I did everything right" when they, you know, actually did everything right and things worked out well. so it basically sounds like entitled arrogant lack of responsibility ... like, "I did exactly what was required and no more and I am appalled that I am not receiving additional compensation." (... tangentially, I also think american tipping culture is really weird and seriously raise the fucking prices and give appropriate base pay. that is unrelated though.)
like when people succeed, whether justified or not, they like to point to miscellaneous factors that they perceived to have helped them out? the basic expectations aren't a recipe for success, they're basic expectations where if you don't meet them you're definitely expected to fail but even if you do meet them there's no implication that you're doing really well...
moreover the notion of "doing everything right" really, really generally reeks of cargo cult practices where someone can perfectly achieve, like, the outward appearance of doing everything actually right, without actually doing it actually right, and then not realize that the essence of the right thing isn't actually captured by the outward appearance they're imitating.
like studying well and learning and internalizing what you've learned isn't actually about doing the homework and taking notes and reading the material ... if you're doing those things because you're thinking that's the right thing to do instead of setting your goal as learning the material ... that's a problem and you're not going to get the material down.
because the reality is, basically all work which isn't getting checked or marked is optional. (this doesn't have much to do with whether there's credit for it, though ... if it's getting checked at all, you should probably do it anyway.) they are recommendations which set a baseline expectation. it is not sufficient to just do them. it literally doesn't matter whether or not you do them, what matters is that you learn the material you're being examined for.
that means effort, like mentally strenuous effort, and that is not the same as spending hours slogging through tedious busywork. there is a substantial difference between strenuous work and tedious work once you experience it. (my experience of it is, strenuous work is actually engaging and even if you still don't like it, it's at least something you can respect after you're done with it. tedious work eats up your time and you don't learn anything, although it does help keep your skills sharp. ymmv though.)
it's not like your entitled to something and they're giving you shitty resources; they're telling you to build a house and they're giving you a stick and a piece of paper, but nobody's really expecting you to use just the stick and the piece of paper for the whole house, and they don't actually have the resources to give you to build a house with because the materials they have can only be used with expensive equipment that they can't just loan out. ... also my metaphors suck.
if you think you did everything right and things didn't turn out okay usually it is because you did it wrong.
if you're in a particularly bad mood and/or not really open to admittedly kind of aggressive-rantish elaboration of what irritated me about that attitude, this might be kind of unhelpful but um.