When you go, look for buzzards perched in the brush or on the ground. If you see any near where you shot the deer, it almost certainly will be close to the kill.
While a mule kick is certainly a characteristic of a good hit, it can sometimes indicate a grazing shot under the belly or also a gut shot. Hair and blood can be amazingly easy to miss, especially if you miscalculated where the deer was standing when you shot. Any kind of vital hit with your load should have blown hair and little chunks of heart/lung tissue along with a splatter of blood out the far side. Check closer and further from your position than where you think the deer was standing. One day later there may not be much left, and it will be doubly hard to find. You do owe it to the deer to look thoroughly.
I use a "pie" grid when searching for a hit deer. The spot where the deer was standing at the shot is the center of the pie with a radius of 200 yards (its very rare for a fatally hit deer to run further than that). Divide the pie into eight slices. Eliminate any slices of the pie that you were observing, so that you know the deer isn't in them. Walk the edges of the remaining slices, paying particular attention to clumps of bushes, brushpiles, tall grass, and especially prickly pear bunches. You will have to backtrack over the outer edge of every other slice. More than likely you will find the deer if it was fatally wounded.
If you don't find it, you certainly aren't the first or last. It does hurt, but bear in mind that in nature nothing is wasted, the buck will feed many different organisms and return as nutrients to start the cycle again. Good luck searching.
