Not a bad start
But hit detection is really off on this. You can't get hit by the gun, and only sporadically hit others with it. As I'm typing this, my character is just standing in the middle of a group of guys at the start of level 2. Not only did he not get killed, the other enemies ended up getting killed by the enemy with a chain gun, while I took no hits. That really indicates how badly hit detection is programmed on this.