Over-thinking it

I am the world's worst about over-thinking things. This is one reason I was such a bad test-taker in school. I would talk myself out of the right answer. It happened again to me this past Sunday night. I prepared to preach a sermon from the book of Hebrews last week. Sunday afternoon, as I was rehearsing it in my mind, I eventually talked myself out of preaching this message, because I felt as though it was too elementary. So what did I do, I prepared another message at the last minute. I was nervous and felt unprepared while preaching Suunday night. After looking back, it would have been better to stick with what I had originally prepared. That's what happens to people who over-think things. Can you identify?