Yes....Yes you should.
At the present moment the yeast sees all of the sugar as food and will not stop until the food is all gone.
This will not hurt your batch, and is not really enough to raise the alcohol content so everything will be fine.
So if you "do not" want flat beer, than you must add more sugar just before bottling.
Secondary #1: MT Secondary #2: MT
Conditioning: Nothing Drinking: Store bought
On Deck: Festa Brew Red Ale....As soon as I get my bucket back from storage.
All bottles are Guinness bottles, Plus Five Kegs!!!