I can tell you from experience, after a fast of seven to ten days when I ate a regular meal, I was bloated and felt uneasy. All my long fasts were broken with fruits, freshly squeezed orange juice. Yes, I gained weight. I have never eaten meats, fish, chicken in my life, so cannot tell you how it feels eating those foods.
If you want to continue to lose weight and stay in ketosis, eat salads with avocados. All high proteins will turn into fat and is very acidic to your body.
I use simple logic, ease into eating after a fast, start low, build slow is the way to go. Also eat and drink per hunger and thirst.