Ooopss 
my bad lol. In that case I suggest you try to sound more natural.
Some phrases sound a bit awkward. They are understandable but they are not the typical way someone would say them in a conversation. For example, "... , and kept hearing something following him."
If I may, a different way to write that section while keeping the same feeling could be: "The boy kept hearing strange sounds as if someone or something had been following him."
Your mind probably skipped a few words while writing. It happens from time to time. I sometimes miss words while writing my novels. That is the reason I read everything I write over and over.
Sometimes a simple "the" or a simple "a" can make the world of a difference if we miss it while writing a story.
Think of the common example of:
It applies to anyone who writes a story. With practice it happens less and less. But no matter how many hours you dedicate to writing it still happens. (As an example, I wrote ours instead of hours the first time but after identifying my mistake I corrected it.)
