Never make your losing streak longer!
If you see you lose a game after game don't make your losing streak longer! The biggest number of games in the ordinary rated tournaments is 22. So there is no sense to play more than 22 games in a row. More than that my personal experience reveals that even 5-10 games is more optimal. You are not to move pieces enjoying the moving itself you are to play your best every game. The crucial point is proper tension and proper conditions.