I've never dealt with a saddled air cell, but it could be both. If your hen laid the egg, and then set on it, its very unlikely to be saddled, as that usually happens to shipped eggs, to the best of my knowledge.
A saddled air cell will look just like a saddle, air cell drawn down two sides and a big V shape membrane. When you have an internal pip, you'll see the membrane grow and in a lot of birds, draw down slightly on one side, then you'll see a tiny V shape poking up out of the circular/oval air cell, thats the beak, so, small. This looks like a shadow inside of the air cell and can move about within a little.
It sounds like you're hearing baby tapping the shell, which is what they do after internally pipping before eventually breaking through the shell. So its either saddled and internally pipped, or the more likely- just internally pipped.
Either way, at this stage it's important not to handle or turn the egg, it's possibly the hardest time of the hatch, waiting! Hopefully you'll have a chick soon!