We all go to picnics and have a cheat meal now and then, if you fell off track, you are not alone.
Here are 3 tips to help you get back on track:
Tip #1 has to do with how you feel about the situation - Don't think you blew it.  All is not lost and you can get your progress back.
Tip #2  No one is perfect, so give yourself a little slack for mistakes and strive to do your best 80% of the time.Start today and you can get that progress back and see results!
Tip #3 Out with the old, in with the new.  If you have left overs, throw it away or give it away so that it is not there as temptation and you can start fresh this week. 

You tube video link for these tips fromme:https://youtu.be/Npq6C2RgkBM