I'm not too worried, I mean obviously everyone has bad games, all of the "greats" (not that romo is yet by any means) or at least the more notable qb's (right now) have had had awful games and lost, manning (big manning) and brady have all had games with a lot of interceptions but their teams lost those games.
The problem at the end of last year was the defense fell apart completely, then the offense tried to compensate. The defense was suspect during the first few games but really picked it up, regardless if they've played poor offenses. I think they'll be fine and have a nice balance, the offense was stellar the first and the defense was "ok" and now the defense has been picking it up, once both getting going, not to disregard special teams, it'll be fun times.
but still, a win is a win like someone said, 5-0 is still 5-0. resiliency is still a team effort, even though romo was definitely to blame for tons of turnovers, he also brought them back into it at the end, it takes some balls to keep your head up with so many mistakes