nice, but.....
you could have made a few improvements. One is that after being defeated, you have to start all the leves over, which is a little annoying. The second one is that after you go back to the menu, the music starts overlaping, but it's corrected after you start the game again. Also, you could have made some sound effect of the gunshots, explosion, and so on. All in all, it's very good for a first time, but it could have been better