- age 14, New York
That is an extremely common reaction, and it's almost certainly physiological (i.e., physical rather than mental) in origin. For most guys, something just shuts their brain off to sex when they're done ejaculating. For many, this manifests itself in the form of guilt – that you were "being stupid" (as you put it), or they ask themselves, "Why did I just do that?" This is all normal, and you'll probably outgrow it as you get older.