First real performance review came back rough and I did not see it coming at all

Six months in, thought things were going fine based on day-to-day comments, then my review came back with "needs improvement" on two things I'd never once heard about before that meeting. Manager said they'd "mentioned it in passing" a while back, which I genuinely do not remember happening. Spent the rest of the day replaying every interaction from the last six months trying to find the warning signs. How do you even recover trust in your own read on how you're doing after that?