Remember Ray Horton's first game as our DC? The rookie Cam Newton threw for 422 yards in his first career game and the Panthers had ~500 yards of total offense.
Give it a little bit of time.
Also, count me among the people who think DWash would have made a significant difference. He's our best defender, and he helps elevate the three things that killed us most today: pass rush, running with a TE when necessary, and limiting the damage in the RAC of short completions.