It was alright, but could use some improvement. "I can barely make out the silhouettes of my three companions" you say, and then you go on to describe how each of them looks without hinting that they went into better light. Your sentences are also choppy and don't flow too well together.
You're talking about cover, then the noises, then about the cover again. Try fitting all the subjects together accordingly.
Try introducing the lack of sleep bit a bit differently. Try something like "I hadn't slept since we've arrived at this place. Every creak and noise was barely registered in the state I was in... I wanted to sleep, but the mere thought of me dozing off only to have one of those creatures (insert whatever they do) to me was terrifying." Try making what you say about terror stronger so that the readers can feel it.
"I looked away for it pained me to see him in this state." That feels out of place with everything else you've wrote. Unless your writing style is old and extremely articulate in such a way, just try "I looked away, it pained me to see him this way." Make sure everything blends together.
Introducing the descriptions of your characters was a bit weak too. It almost seems forced. "Her chocolate colored skin and brown eyes were the opposite of my unnaturally blue eyes and light brown hair." No character in this situation would think this. Introduce the main character's description through a reflection of some sort, or "My __ hair was flying in the wind... Deep ___ eyes alert.... etc." Try something like that. You try to sneak in descriptions of what the characters are wearing, but it doesn't make sense to say "I then realized we were all matching when it came to our worn down black sneakers." Why is your character thinking about the squad's matching sneakers in this situation?
"He smirked. He always found a way to get on everyone's nerves." Why does smirking get on their nerves? In what ways does he get on everyone's nerves constantly?
"ramming down the door with a table... zombies" I think you should explain the zombies. Are they actually intelligent? If so, why didn't they just open the door as opposed to ramming it with a table? And how does one ram a door with a table?
That's all I'll do for now. I think this may have gotten a bit long.
Overall: Work on the way your sentence flows, explain things a bit more, make sure everything makes sense, and try to make certain scenes longer.
