One teaspoon is normally about 5g, maybe 10g if fully heaped, so we're only taling 4-7g of carbs..... Probably not too lethal. But if the milk is low fat you may be having too many carbs in the milk.
But reading the blurb, they seem to be advising it as a cereal alternative, and T2s generally don't do well with cereals.
I guess the real question is, why are you taking it? Fibre, vitamins? Do you like the taste?