To be afraid is good, after all, it will help you to be conscious towards excessive risks.
However, you should learn the contexts of proper financial conduct and money/risk management in gambling before you do anything. Also, ensure you gamble only with the money you can afford to lose and have a good gambling plan, and be disciplined to stick to that plan regardless of the situation or how you feel at that time.
Risk management works very well for me by limiting my bet size to no more than one percent of my bankroll. There is nothing complicated about it, you just always follow this rule. Breaking it is simply forbidden. And this alone can save you from many problems, big losses, bad moods, excessive emotions, and much other negativity that you will experience if you lose more than you can afford.