[Noob] Is it ok to drink 1-2 True Lemon Packets with 3g of sugar as long as I am under 20g of net carbs?

I started Keto Last monday (4.17.17) and have been keeping net carbs <20g a day. I drink 1-2 of the True Lemon packets, but I just found out that the ones I have been drinking has 3g of sugar in it!

Would this interrupt ketosis (even though i stayed under net carbs of 20-25g a day) since it is sugar? Was the past week for naught? Or am I ok? I am switching to the True lemon with 0 calories here on out.

Thanks!