Is there a limit on the amount of protein you should eat in one meal?

Protein is going to fall under calories in/out just like every other macro. If you are eating in a deficit overall, you'll lose regardless.

https://www.youtube.com/watch?v=CTF9YR6BU9k

You will probably like this video.

Point#3:
"Let me be crystal clear, you absorb and use virtually 100% of everything that enters your gastrointestinal tract from your mouth. If you don’t, you’ll know it because you’ll be having watery diarrhea post-prandial (after a meal) since the undigested and unabsorbed food will act osmotically to draw water into the large intestine and then well, you know what happens after that. Look, we’ve done the tracer studies and know that when you eat any amount of protein at a meal it all gets absorbed. All of it. Actually 110-120% of it. Yep, MORE THAN 100%. That’s because the cells the line the bowel, the enterocytes, make proteins themselves. These are called endogenous (made within the body) proteins and yep, they’re absorbed too. Yes Virginia, if you eat 100g of protein at a meal you’ll absorb it all. Yes, it will take longer than if you only ate 20g, but you’ll absorb the first 20g of protein from the 100g at the same rate as 20g on it’s own provided they have similar total fat content and fiber content within the entire meal. That being said, the time course to which a meal is absorbed matters little to anyone, unless they compete or train multiple times per day."