All of my trades start with a trading plan. That means I know what conditions I need for entry and exit before I ever execute a trade.
Some trading plans are more defined than others such as my condor trades and some might be based on crossing a particular moving average, stop loss or profit target. Typically I try my best to follow my trading plans. Sometimes because my experience I will let a trade continue a little longer than my plan calls for or place a hedge trade to offset any losses and let the trade run. I have not really researched how often this has paid off but my guess is about half the time a slight modification in a trading plan can become profitable. The rest of the time you just increase your losses.
My suggestion to you is follow your plan. Do not look back. What kills traders is fear and greed. Fear that you will make a mistake and greed that you could make more money if you just waited. I am convinced that the market knows when I exit a position to stop my losses and then the stock reverses and I look at all the money I could have made.
Have a plan. Stay on the plan. Do not look back or worry about what could have been.