I don't like getting cocky or even confident about a game either but I remind myself that my superstitions have nothing to do with the outcome. I felt the same way about the game this week. I was very confident about the Rams' chances. They had outplayed the Buc's the last two times and regardless of outcome, they clearly were capable of winning.
The Rams have worked their way into being the better team and should be confident about winning. They have been outplaying SF, they just have to not let up. That is far different than SF's overcoming better opponents and miraculously pulling out close wins after coming from behind.
It is far less likely to continue living their way compared to the Rams just capitalizing on the huge leads they are establishing.