BookRix

I'm in agreement with Judy. My advice (like hers, generally) is get an editor. A teacher schooled in English, or a friend/writing partner/group. Those impartial, different sets of eyes, will catch many errors that you as the writer just don't see. Things like, "I could of..." take the reader right out of the story. You might want to (should) delete "of" and replace it with "have". Ie., "I could have..." Even, "I could've..."
"I use to..." No, "you USED to..." These are small things, but they separate the seasoned writer from the novice.
Check your tense agreements throughout.
Check for correct punctuation in dialogue..."Chester went to the bathroom," he said. I replied, "I know..." Like that.
Check for correct placement of commas preceding conjunctions.

But...Nice job overall.

One last thing...Your protagonist's friend. Real young people DO use fuckin' every other word, and I know you want authenticity, but consider...just consider...eliminating a gob of them and replace with something else. This is literature. You can make his friend dim-witty, but do consider cleaning up his mouth, lol.

Impressive! Excellent plot and great horror. It needs a lot of editing (formatting the dialogue, spelling, etc.) but otherwise this is terrific! And I love how you handled the ending, which is all I'll say about it so it doesn't spoil things for others who read it. ')