Couple things for you here. When you say you added an extra ingredient, what did you add? If the room temperature was 70 degrees, your beer was likely fermenting 5-10 degrees warmer than room temp. This will tend to speed up the process but may also lead to some off flavors produced by the yeast fermenting so warm. What yeast did you use? 1.028 will result in almost a 7.5% beer. The recipe according to NB should produce about a 4.5% beer so this will likely be boozy tasting.
That being said, I would definitely let it sit for at least another week before attempting to bottle. Even if it looks like fermentation has completed, the yeast are still working to clean up after themselves. Typically you would want to leave it for at least two weeks. The easiest way to test if it's done is to take a gravity reading 3 days apart. If the numbers don't change, it's done.
Take a look at Some of these posts regarding swamp coolers to help you keep temperature down during primary fermentation. I'd also recommend one of those temperature strips to stick on the side of your fermenter to give you a better idea of what temp the wort is fermenting at.
Go ahead and ask any other questions you may have, we'll be happy to try to help out.