“I get mad when my teammates make mistakes.”

That frustration might mean you care. But if it leaks out wrong, it makes the team worse. Your teammates can feel when you are judging them. Then they get tighter. Now the mistake grows. Leadership starts with your face. Next time somebody messes up, say one useful thing. "Next play." "I got you." "Shoot it again." Keep it simple. Then hold yourself to the same standard when you mess up. If your standard is high, good. Just make sure your presence helps people reach it.