Without anymore disassembling of the camera you will probably not be able to find any damage. And since you dropped it inside a bag inside a bag, where at leased one had also padding, there should not much happened. Expensive cameras in this class are normaly build like little tanks and are made for taking some abuse, since they are used as work tools. So dont be too worried. Just take some photos and videos, use every button and wheel and lever on the camera, also shake it and hear for loose things (attention there might be a normal rattle in the camera, since in older models they used a little steal ball inside some cage to know which orientation the camera has), slowly use the rings on the lens and hear and feel for not so good sounding stuff. See thru the front of the lens and move it slowly, so you could find a possible loosing of a lens (yes i had one in the past :( ), try to rock the lens on the camera mount and check the mount that it is still perfectly plane (weight of some lenses can bend the mount in some extreme situations)

But in the end you cannot fully check everything. There is always a risk left.

I also had a super freaky lens failure, where an inner guide bolt for the inner zoom tubes got loose and jammed the whole lens to garbage.

And if you still unsure: Send it to Nikon for a full check.

(And damn what a nice camera set you have and what a cute cat :) )