There is no problem with the flow of your story. There are a lot of run-on sentences however, which a beta would probably advise you to split.
If you read some of the good authors on any archive you will see that they use both longer and shorter sentences. Short sentences, even fragments occasionally, can give great impact. It is good to have a mixture.
Here is an example by a superb writer, Darth Fingon.
It started when I was in late youth. Not yet married, but grown out of childhood, I was too old for them to take when they gathered all the boys of our village and marched them east to Caras Galadon. To be educated, they said. They would teach those boys how to read and write, how to use a bow and a sword, how to speak better and how to act like a proper grey man, even if they were Lindyn by blood.
See how he uses short, pithy sentences for impact and longer ones for flow?
Long sentences do tend to loose the reader at times. It draws the eye on in a hurry and by the time one has reached the end, it can become tangled.
I have read extremely long sentences in published works and fanfic, but they are always punctuated by commas or semicolons which allows the reader to pause at those points.
You do need to add commas in some of these long sentences, if you want to keep using them.
On the narrow boardwalk that lay before him there were few locations in which to hide from his attacker (comma) but due to the fact that whoever was after him was close by (comma) he cared less about the quality of the hiding spot and more about simply finding one.
could of - people seem to write that instead of could have. 'Could of' is not correct English.
I am only pointing these things out because I think you obviously know how to get a story flowing and create characters, but a beta would really help you. They would show you how to balance out the sentences; they don't all have to be long and involved or all short and choppy - a good story has both.
Good luck and happy writing.