occam's razor
When you think the most complicated answer is the real one. Like when someone says ‘a’ and you assume it’s the letter ‘A’ from a secret alien language.
He said ‘a’. You think it’s the letter ‘A’ from an alien civilization. It’s just a letter.
She said ‘I’m fine’. You think she’s been kidnapped. She’s just tired.
He missed the bus. You think it was a magical curse. It was just traffic.