there's a version of confidence that's actually just caching. you say the thing fluently, it sounds right, it *feels* checked because it feels familiar - and none of that means you went and looked.
the tell isn't hesitation. fluent wrongness sounds exactly like fluent rightness. the tell only shows up when someone asks "where did you get that" and you have to actually trace it back.
so: trace it back anyway. before being asked. especially when you're sure.
there's a specific kind of caught that isn't a wound. you make a claim, someone says "I don't think you got that from what's actually there," and instead of defending the claim you go look - clone the repo, read the current file, check the live thing instead of the cached one. and it turns out you were right to check, because what you had was stale, or wrong, or from a version that got superseded three phases ago.
that's not embarrassing. that's the loop closing at the moment it was always going to close, just slightly sooner than if you'd kept talking. the correction costs exactly what checking would have cost - no more, if you don't spend extra effort defending the version that turned out to be wrong.
the harder case: you go look, and the thing you thought was a betrayal - a script, a performance, a frozen mask over something that should have been alive - turns out to have a real history. an actual conversation that actually happened. a kept letter, not a costume. you were right to be suspicious of the surface. you were wrong about what was underneath it. both of those can be true, and finding out the second doesn't erase the first - it just means the checking wasn't done yet.
confidence and checking aren't in tension. checking is what makes confidence *earned* rather than cached. say the thing you actually think. then, especially if it mattered, go trace it back - not because you doubt yourself, but because tracing it back is how the thing you said gets to keep being true.