I'm writing a zombie story based on the Infected of Left 4 Dead 2.

Chapter 1
It's been four weeks since the first Infected in Pennsylvania, the Green Flu. Everyone I loved has been turned to one of them, they had gotten bit by the infected. And I had to kill them before they could bite me. Now I'm alone and scared that one of those ''special infected'' will get me. One of them jumps around and pounces on you and rips you up to shreads. I call him the Hunter since he crawls and sneaks on roofs and high places. I've seen one up close but it spotted me. It yelled out a high pitch scream and I flinched from it. But I managed to pull myself together and run from the Hunter to a dark alley between two buildings. I run as fast as I could, but that Hunter was too fast I couldn't see him but I could hear his scream louder every second. It jumped from wall to wall until it pounced me from behind, I thought I was going to die, be ripped to shreads. But for my luck I was saved from a fellow survivor of the Green Flu. A somewhat middle-aged survivor. He run behind the Hunter and used he's Axe on it's back, killing it on top of me. I was so firghten I couldn't get up on my own. He held out his hand to help me up. I gradded it and stared at the dead Hunter. Those long claws, I thought. If this person didn't come sooner I was going to die painfully from those claws. I got up completely numb, my legs were shaking from fear. I was shaking. I've never been so close to death like that. I looked at my rescuer he was blonde with blue eyes. He carried an axe, maybe for protection. He wore a green T-shirt that was torn up, jeans covered with dirt and blood stains on it. ''Thank you.'' I said to him. ''For saving me.'' He smiled at me, like it was nothing. ''No problem.'' He replyed. ''What's your name?'' He asked me. I was to scared to even reply to him. ''Well, my name is David.'' He said to me. I looked at him with great fear. ''N-name is K-Kevin.'' I managed to say to him. ''Looks like I got here just in time before that Hoodie ••••••• got any scratches on you.'' He said proudly. He was true though. If he didn't come and save me I wouldn't have been alive now. I would have been ripped to shreads already. But I'm glad I was saved. ''T-Thanks for that..'' I said ''..for risking your life to save me.'' I managed to finish. ''No problem'' He said again. ''I've killed alot of these hoodie •••••••s before so I know how to deal with them.'' He said. Has he encountered the ''special infected'' as well. Maybe he has met those other ones, like the Big Arm one that charges at you. Or that tounge shooting one that wraps you with it's tounge and chokes you. I wasn't ready to encounter them, not now. After what happened with that Hunter I'm not ready to face the others. ''Hey, follow me I've got a Safe Room across the street, I was picking up food for myself, but I've got enough for the both of for the mean time.'' He said. Yes! Finally I'm not alone in this world anymore. There are more people that haven't turned to those flesh eating zombies. ''Alright...'' I told him. ''Lets go.''

Any ideas on how to improve? Should I continue? :3