Lose and Gained Weight

I lost 4 pounds and I gained 1 pound again because of the ruined diet last Tuesday night at the get together Christmas party at my friends house. Plus the uncontrolled eating of carbohydrates yesterday and no exercise as well. I will make sure not to eat any carbs and to do my workout today. I need to lose weight!!
I am thinking of starting the 7 days diet again from the start tomorrow to make sure that I will lose enough weight before I go back to work. I seriously need to lose weight before I have my vacation in the Philippines on February