Considering that I am in the shoes of the detoxee - all I can say is that he made it to 10 days - that's HUGE. You should be really happy about that. I know you don't understand it but I'm telling you that the first 7 days are absolute hell. He is over a really huge hurdle. He has a good start on recovery.
Opiates are just unbelievably addictive. He has a chronic mental illness now - but the good news - he can put his illness into remission himself - with a lot of treatment and hard work.
I know this sounds stupid to you - but the truth is that he does have a disease. It is a disease in his brain. If he got cancer you wouldn't be so angry would you? I know it isn't the same - and you don't understand and of course you don't. He is a big liar. Lots of us here used to be liars. Lots of people that you would never guess to be - are recovering addicts and lots are still active addicts. It is more widespread than you can imagine.
Your son has a great chance at recovery. I do suggest that you learn as much as you can about this disease. It is baffling, cunning and powerful. Heroine, alcohol, painkillers, etc. IT is all the same disease with a different drug. And it can effect anyone. The more knowledge you have - the better your future will be no matter what happens.
You have found a very good place to vent and to ask questions and get opinions. Lots of people will pray for your family.
Oh - and on what to do. There are so many ideas/opinions/experience on this subject. That is why knowledge will really really help you. (However - if it was my kid - I would definitely buy home test kits. )