I think Josh is a little overconfident - not cocky, but a bit too sure of himself at times. In the previous three games, he put the game on his shoulders, took too many chances, and made some costly mistakes. But he rallied the team in the fourth quarter and got three wins, so he figured he could keep doing it. If he hadn't been injured, it's possible that he would have pulled off a game-winning drive today.
Hopefully, this is a wake-up call for him. Fourth quarter heroics can't always make up for undisciplined play earlier in the game.