I'm really beating a dead horse here (
) but you really have nothing to worry about with the carbs in cottage cheese. I personally love cottage cheese as a late night snack and eat it without any worry about the carbs in it.
In all reality, even if you were to have a scoop of ordinary protein powder you would get somewhere in the same range carbs wise. For example ON 100% Whey has 3 grams per scoop and their 100% Casein has 4 grams per scoop. Little facts like that always send me back to reality when I start worrying over tiny amounts of carbs.