Graphics/animation were okay and this had all the basic factors of a good shoot em up game (point system, blood, crosshair). What I liked was the gun: the detail of it was great and I liked the animation you added there.
Nice job on including different music btw. However, the sound clips got annoying and could be lowered down a bit or be able to be muted :P
However, the concept and gameplay is nothing really original: there are tons of these games on NG. Add some more stuff to it.