Then the beer will be a little higher in gravity than the original recipe. No worries, but you will have to procure an additional 5 oz of priming sugar when it comes time to bottle.
That depends on when you are talking about adding it. You add it at bottleing time so that the yeast eat it. The co2 they create can't escape the bottle and it carbonates your beer.
The beer will only have about a .0005 % more alcohol by volume, so you won't notice anything different in the finished product really. And you will have to add more sugar come bottling day.