Did you binge on sweet sugary foods or alcohol recently? Don't worry. Better if you don't, but if you did, empty out some glycogen by doing some high intensity exercise (research what that really means) and get back to your low-carb diet. If you want to, you can also fast for 24 hrs to get your hormones back under control, specifically insulin and glucagon.
You will be back on track in a very short period of time.
Humans evolved in alternating states of feasting and fasting.