It could be different for other people, though. However, gambling while bearing a negative feeling is not good. Negative feeling equates to bad luck.
This is just a superstitious believe by some gamblers because it's not totally true that when you have a negative feelings it will affect your luck, these luck in question happens randomly irrespective of how someone is feeling but being anxious is just like a natural feeling that some people have when they go gambling because they are scared off losing.
Right! Anxiety is natural so being anxious is one of the human traits, because someone is not positive about something they can be anxious and at the same time it will work out more than they expect one can also be positive and anxious and it goes side ways so having negative feelings has nothing to do with anxiety, if you’re worried about an uncertain outcome you will be anxious and behave in an unlikely manner that’s just one thing about anxiety and nothing more, the only threat it poses to your gambling is that you can hit the wrong button or cash out when it’s premature because you’re anxious.