Give the kid a break. He's a rookie who started in his third ever game in the NFL and it showed. He has no veteran mentor outside of Nate Peterman, an OC who and QB coach who never played the position before, WR's who can't get open to save their lives, a running game they're not even using to help him out, and let's not even discuss the O-line. Granted he's going to make his share of rookie mistakes (holding the ball too long, misfires, asinine decisions under pressure that lead to foolish INT's) but still, what does he really have to work with? Opposing DC's are going to throw everything including the kitchen sink at him to screw him up and throw him off his game.
It's going to be a brutal learning experience for him, but he can only get better from it.