That IS short. From the pic, gunner, it looks like you are in good shape. Like what my hair looked like when I first buzzed my head, although you have signs of some receding at the temples.
I think it might look kinda weird to use a concealer on such short hair. No one in the world could conceal their scalp with hair so short. It might look unnatural.... BUT... you should try it and see anyway. I could be completely wrong, it might look good. From what I see in the pic, however, I think it looks fine as is.