Protein... birthday?

Yesterday was my birthday and also protein Thursday. I though about it for a while and decided to honour the protein days and do my celebrations on the weekend instead. I was doing so well the whole day.. up until the evening where (to my surprise) the men in my life had planned a birthday supper at a restaurant. Usually I'm always aware of what goes on so this really took me by surprise.
 I was attempting to stick to the protein rules but as soon as the menu came out that went out the window. I ate 1 piece of garlic bread with cheese, filet mignon (rare) with pepper sauce, caesar salad and some rice and potatoes. I did show some restraint with the rice and potatoes and only ate one bite of each.
 I was expecting to have gained or at least stayed the same weight as the day before but I did end up losing a little bit. Not as much as I usually do on a pure protein day but enough. I am right now contemplating if I should make today a protein day as well to make up for the birthday cheats or if I should continue as normal but as of this moment I haven't quite made up my mind.

Weight recap for the week:

November 16: 137.0 lbs (celebration meal: cheese/bacon burger, fries, ice cream sandwich, chips)
November 17: 138.4 lbs
November 18: 139.4 lbs
November 19: 138.3 lbs (whole wheat pasta day)
November 20: 138.6 lbs (I baked cookies... I should know better)
November 21: 139.8 lbs (cookie shame weight gain along with the botched protein day)
November 22: 138.4 lbs