I think in Ryland's case its gotta be something stupid, maybe a slash call that wasn't intentional or something. He would probably feel a mix of frustration and disappointment, knowing that his team will be at a disadvantage for a couple minutes, probably throw some f-bombs that aren't entirely directed towards anyone. But, things happen in the heat of a moment and sometimes players don't really recognize what they do until after the fact. He'd skate to the box quickly, trying to avoid arguing with the referee to prevent an additional misconduct penalty. In the penalty box though, he's gonna use his time to mentally regroup, watch the play to see if there are adjustments he can make once he's back on the ice, and cheer on his teammates to kill the penalty effectively. He'll remember who he slashed and probably after the game, offer him a beer or three on him.