I have liked this girl for a while her name is Katie. But last night I had a dream about another girl.?

If you've never felt feelings for this "Brianna", then it probably doesn't mean anything. Don't let this dream get in the way of how you feel for "Katie". A dream can't tell you who you like or who you don't. If you really like "Katie", this dream shouldn't get in the way of how much you really love her. My advice? Forget about "Brianna".