It is probably still fermenting even though the airlock isn't active. Don't trust an airlock, trust your hydrometer. If it has truely stopped, a hydrometer taken in the span of a few days will be the same. If it is stuck, use a little yeast energizer/nutrient to get it going again. Stir/swirl it in, don't shake. Oxygen in the cider is asking for problems.
Your thinking is right about 4%, but the method is difficult, especially for a beginner to accomplish. Thing is, even if it is a stuck fermentation, something will happen to cause it to start going again, like bottling or something. Anyway, since this is your first batch, let it go dry and see what it is like.