So happy for you!
You will do FINE, to be sure. I went off plan on Mother's Day myself. Enjoyed the day and got back on track, using the great tools I've learned on Spark.
The old me would have used that day to say, "Well, I've blown it: I might as well eat X, Y and Z!!" The new me says, "That was yummy! Okay now, what delicious healthy thing can I have for my next meal?" Just like that.
Like Nancy said, it's not a day or two of over indulgence that gets you heavy..it's doing that day after day after day after day.