For Nick: He sustained an injury to his arm ('I hurt my arm') and was very dangerous. He also lost the competition, implying that the accident occurred during or affected his performance in a competition.
For Brian: The excerpt doesn't detail any direct consequences for Brian, other than being identified as the cause of the accident and the one who 'cut' Nick off. He is also mentioned as having 'won' the competition, suggesting he was unaffected or even benefited from Nick's misfortune.