you are right that in trading we have to be disciplined, and make you strategies more useful while following the same trading plan when ever you trade you don't have to look that how much you are loosing or earning in a single trade all you have to look is that you must stick to your trade plan that is if you are making some profit that you first hoped before the trade then you much take that profit and close your trade and don't get into greed and loose that all that you have earned