Just because your FG was in the ballpark of the recipes doesn't mean it didn't drop a bit more. Really, there isn't much difference between 1.008 and 1.012, and no one can tell you exactly where it will end.
But, still, airlocks bubble for a variety of reasons most often changes in the weather. Warmer liquid will release co2 more readily than cooler liquid, so if the room got a bit warmer the airlock will bubble. Barometric pressure can cause a change of the pressure inside the fermenter, too, causing airlock bubbling. In other words, it doesn't matter a bit if it's bubbling or not.
What matters is that the gravity isn't changing over the course of at least three days before bottling. Check the SG today, and check it on Saturday or Sunday when you plan to bottle. If it's the same, it's fine to bottle it.