Emotion is just a normal part but doesnt mean that it would affect luck chance for you to win the game. There's no factor that could affect your winning probabilities.
Yeah it's normal and in general doesn't affect the luck of the games we are playing at all nevertheless I believe that emotions also could become one of the factors to encourage winning probabilities. Why? In case someone is carried away by his emotions while gambling I'm pretty sure his calculations or decisions that he made at the time would be mess up the gameplay particularly in several card games such as BJ or poker with certain decks.
As you say your emotions do not change the probabilities of the games but can surely change the outcome for you if you are unable to control them, if you are a professional gambler and you can actually beat the casinos if you lose control of your emotions then very soon you're going to lose money as well, and even if you are not a professional gambler and you do it just for fun if you lose control of your emotions you could find yourself very quickly in a difficult situation that you were not planning to get into because you simply lost control of how much money you are betting.
in short, it is how you react with your gambling results. but definitely, most gambling games are based on luck and not your emotions. the outcome has nothing to do with your emotions. but whatever the results are, it is how you approach the outcome. many people are just associating some kind of "voodoo" rituals thinking that it may have effect on the results, but i believe it is only psychological as it has nothing to do with the luck you have in winning games.
That's right, your reaction to the outcomes that you get matter, if you are able to take a loss and still remain calm then even if you lose money if you are not going to lose that much because you are going to be still in complete control over yourself and your money, but someone that loses and then goes completely crazy and loses control of himself has a very high chance of losing the rest of his capital simply because he is unable to accept a loss.