I ate a whole medium pizza to myself and then a crepe for dinner last night. will this ruin my weight loss efforts? did i gain permanent weight?

No: but if you do this everynight it will. Exercising and eating healthy will put you on the right track to losing weight and keeping it off. Avoid nightly binges.

No : You went on a binge eating episode !! You did not ruin your weight loss effort permanently , but you Sabotaged your weight loss and that happens . Forgive yourself and move on . You probably retained some fluid from the salt that was in the cheese and toppings and sauce in the pizza . Try to do better exercise harder in the coming week to burn off these calories that you ate .

It might: From your history of depression and being on anti depressives , I think this binge eating may be stress induced. To avoid future binges it's important to meet with a psychologist to take care of deeper issues . Otherwise you may continue to gain weight from these.