hey man not too bad!
dammit that was great. And i know this comment may annoy you and i'm guessing you actually don't care anymore about this game but the enemies were easy + you could only shoot them in 2 parts - head or chest - and it would be great if you could shoot them elsewhere such as kneecaps etc.
anyway, keep it up!
P.S: you might want to put the ammo and health layers below the cursor/pointer/crosshair layer. You'll see why...