The limit on your test kit's ability to read chlorine is 5ppm. So, is it really 5 or higher. Use this link and tell me what you think it is?
http://pool9.net/oto-chart/

How consistently are you maintaining shock level? It has to be consistent or it will take forever to clear up.

Yes, run the pump 24/7 while you are working to clear it.

Why don't you do yourself a favor. Buy the Taylor K2006 or 2006C kit. It will make this clean up a lot faster and easier. http://pool9.net/tk/

Do you fill from a well or city water?