It all starts with small amount of losses until it grows, until the emotion comes in and control is gone. Until you can no longer feel of what you are before because what's important to you is to win back your money. That's why you become quick to anger, hard headed and you listen to nobody. That is near to the utmost bad effect to a gambler. If by simply talking to you, you're no longer chill and you get easily mad by few talks. You better sign up for an expert that will assess your behavior because you might be having a behavioral problem that's very common to gamblers.
It is best to address your potential problem at the early stage rather than when you are already deep with your gambling activities. If you are already seeing that you have the tendency to have such emotions that are not in your normal mode, better pause and ask yourself what you need to do next. Because if you won't address it right away, you will regret it later as it is hard for you to change your situation anymore.
So it is not about the amount that will define gambling as a problem. But as long as it is already affecting your financial aspect, you should start evaluating your gambling activities and alter your path that will change the narrative of your gambling life into a more acceptable situation.