Hi Janeygoffin,
Sorry to hear your going through such a hard time with your Son.
I only joined this site yesterday and have had some great people to chat too, and so many people going through exactly the same.
If your Son is asking for help then perhaps he is ready to get serious help, does he say what kind of help he wants?
I don’t know anything about Heroin, my own experience with my Son is cocaine and alcohol.
Speaking to your Sons Doctor is a good starting point, see what he says and go from there.
Let me know how you get on, take care.
Dx