As long as you are a trader you must experience losses and gains, because that is what trading is all about. a professional trader can also lose money in trading.
But the difference between a professional trader and a beginner trader is that: professional traders understand how the market is going, and they have experience on how to minimize losses and effective risk management, but they cannot prevent themselves from losing, that is a fact about trading.
no matter how perfect or professional you are, you must loss in trading. But the foolish among them are those who give up easily when they lose. not knowing that the lose is a mistake, that they need correct and also learn from the mistakes, by getting some experience that will make them stronger, and more professional.