I'm sorry but i don't buy Dufresne's transformation into a hardened bad ass in season 1

Just watching the show for the first time and just finished season 2 episode 1 and Dufresne is walking around like some tough bad ass pirate leader now, after being a meek little scared quartermaster all of season 1.

He gets pushed into 1 small battle, and he's shitting his pants the entire time, and he bites the guys neck and kills him and after that suddenly he's getting a tattoo, shaved his head and now he's bad ass, i'm sorry that was dumb.

I could maybe buy the transformation maybe halfway through season 2 if he had a few more battles and experience killing, but i'm supposed to believe after 1 fucking battle where he only fought 1 guy now he's large and in charge, confident and giving orders, being all tough and trying to take over. Bullshit, no one changes that damn fast into a completely different person.