Based on other posts I've read here, a stall is technically a period of 3-4 weeks with no weight gain AND no loss of inches. While not a visually exciting video, I like
Bowulf's YouTube video on the subject.
If you had alcohol and artificial sweeteners over the weekend, your body may take a while to burn off the excess calories which would halt ketosis. After that, it might take a couple days to get back into ketosis so a week without a loss should be no cause for alarm. Who knows? The stress/anxiety you are having over the scale may be yet another reason for your body to hang on to the fat stores. Frankly, I think you should focus on the positive: the scale may not have gone down this week, but after a weekend of alcohol you haven't GAINED either! Could be a lot worse.
Hang in there, and stick to plan. Give it a couple more weeks before getting nervous. It may just be coincidental that you are having a mini-plateau as your body adjusts to your weight change about the same time that you had family in town and you are blaming the wrong issue.