It's taken me nearly a month to get back on track properly hun!
The damage can be limited by Tuesday and you may not get a gain but it depends what you had on holiday. Just do the best you can and you'll be just fine.
Good luck!
How much did you have on holiday...I know you don't want a gain but I find it easier to expect a small gain when I go away and allow the treats and that way I do find it easier to get back on plan