A crush you have for an extremely short period of time, and then a couple days later, you're wondering what you ever saw in the person in the first place.
Sally: I have a confession. I like Billy!
Ann: That guy you're always saying is so obnoxious?
Sally: Yeah, but I found out he's actually really nice!
(The next day)
Sally: Ew. Billy is so annoying! I can't stand that guy!
Ann: Weren't you just saying how nice he was yesterday?
Sally: Yeah, I guess it was just a rush.