I.P.
I have one daugther and my experience with her was little different but I trained her to go using a video.
I allowed her to watch it and I was with her singing the songs.
I coud tell that your son needs to learn to communicate his need. I'm sure you can teach your son. I was taking my daughter to the bathroom every 2 hours.
I said her name and then "Is time to go" or potty time.
like a game
She learned very quickly.
Also patience is very important.
I recommend you the potty video You don't need to buy a new one maybe the library has one available to take home.
here is a web for information on that subject.
http://www.pottytrainingconcepts.com/CTGY/How-to-Potty-Tr...
Blessings to you.
Bell