Have you ever truly felt déjà vu, the sensation that you’ve already had the experience you’re currently having?
My opinion on it is more of an interpretation made by the brain based on many factors. To answer the question itself, I can’t recollect any particular instance. HowStuffWorks has an interesting answer to it in scientific terms. In other terms like psychologically, it’s a matter of head being messed up, in a manner of speaking.