Which method of low carbing are you following, ie Atkins, IPD etc, as they will all tell you how to work out the amounts of protein you eat at each meal.
For instance IPD say that meat/fish portions should be a piece the size of your palm and cheese the size of a regular matchbox.
In a day I might eat:
B 2 hardboiled eggs with celery salt
L Tuna mayo green salad
D Pork chop with buttered cabbage and cauli mash, sugar free jelly & cream
S 2 babybel cheese
I don't count the amounts of protein I eat, instead I eat green leafy veggies with protein as part of the meal.
The amount of protein isn't as important as the carbohydrates and as long as I eat a sensible amount then I don't get hung up on it.
The more I count of the different elements means I am more likely to stop because it becomes too much of a chore.