Planning on making a short novel

"Sergei, it's no use!" said Anton, "No one is behind that door. The Brahmin was wrong. Let's not go out like cowards smashing at a door. Let's show these bastards how real men fight!" he yelled, raising his fist into the air. His short speech filled us with visions of dying in a blaze of glory. We all turned around and raised our rifles. I turned on my night vision, now that I was looking away from the dim light hanging above the door.

"I see 8, no, 9 in the front and about 10 right behind them. Looks like they're going to hit us in waves" I said, raising my rifle, pointing it at the mutant ahead of the pack.

"Fire!" cried Anton firing his Kalashnikov like a mad man. I guess when you're about to die there's no need to make every shot count. Only after we all had run out of ammunition we realized the second wave was already mobilizing.
"Andrew and Viktor, use your side arms. Everyone else, reload your rifles, hurry! I don't want to die after only the first wave!" yelled Anton. I quickly dropped my rifle and pulled my sidearm from it's holster. I started to open fire, knowing my pistol doesn't hold much ammunition in the clip I made sure every shot hit. After the fifth shot I heard something. It sounded as if someone was bending old rusted metal. No it can't be, we already tried... but it was! I turned around to see the sealed door wide open with four heavily armored soldiers. Their entire suit was shining from top to bottom, but what I saw surprised me. On the front of their helmets was the five pointed star.

Just corrected the mistakes I saw at first glance.
Your story is alright, though

 

That's a bad idea. Since Dmitry Glukhovsky owns the publishing rights to anything and everything Metro, as well as the copyright and all that, you'd have to contact him before trying to make money from fan fiction based on his work/set in his world. If you don't get permission and don't sign some stupid deal with him, then you'd break international law and would likely have to pay a looooooot of money. People love to make cash from copyright nowadays. Of course, releasing it for free is legal, but you cannot charge for it. You should read up more on that since it's very important and relevant if you want to write that book.

 

He knows a surprisingly large number of languages and English is one of them, but I am not sure how to contact him. I will let you know if I ever come across something useful.