No, it should be just fine. As long as the airlock is intact, the wine should be fine. Sulfites work as a preservative, but they aren't strictly necessary. I don't have an so2 meter, so I "guestimate" my additions at one tablet per gallon at every other racking which is supposed to approximate 50 ppm. Since you haven't racked, you probably are just fine- just like when you bottle. You add it at bottling, but the sulfites disapate with time.