Hi! Welcome to the Shipbucket.
I have to say that this work has, unfortunately, some shortcomings. One is that the contour should be black, but just one-pixel-thick - on Your drawing the upper half of the hull is outlined in non-black colour, while at the same time road wheels, gun barrel and fenders are 2-pixel thick black lumps. There are some heavy corners and shading seems to be inconsistent in general.
You may wish to look at BT-5 made one of our most talented Artists and think of the differences:
http://shipbucket.com/vehicles/7465