Haze Grey is the official US Navy paint color. That being said keep in mind that these ships are only ever painted from the same production batch of the color one time (when first launched into the sea).
After just a few weeks even pierside they will start to get variations in the shade of grey due to a number of things.
Rust, repainting from different batches of paint, repainting in a different climate will even cause a difference in shade.
Additionally every single welded protrusion will develop a tint of rust color and that color will follow gravity as it gets older, most often this is just painted over, but the rust "bleeds" through the paint discoloring it and ultimately layering atop it.
So far this looks great. I'd like to, as a Navy vet, thank you for the hard work.