Hope you had a good birthday. You may have gone over a bit, but the food was healthy.
Fitting the cake in may be a bit tougher, but it is your birthday, and it is better to make a few concessions, than to just take the day off. Lamb, potato, and salad, sounds great depending on what you drank, and what salad dressing you used. I wouldn't worry too much about it though. Even if you went over by a few hundred calories, averaged out over the week, it will make no difference at all, if you eat in range the other 6 days.