Yeah, I guess I have something to blame my amateur coding skills on! Sorry I didn't reply earlier.
The song is quite repetitive, but I only had half an hour to make it. Probably should have just got one from the Internet, but oh well.
I've only finished the game once. And also, press 1 and 2 to switch between ammo. The ammo is not bugged (at least it wasn't for me) it is my bad design that is.