I have never been in this situation before and I have no idea what will happen, but it sounds like your heart is breaking and I just wanted to tell you that I am thinking of you and so proud of you for being honest and telling your doctor, as well as for getting off the oxycodone on your own.
Let me know how things go. You are a strong person for this.
Lots of love.
Good for you for getting clean and being honest with your doctor. Its going to depend on the county you live in because they all have their own rules. You could try doing a Google search for your area. I know where I live doctors are under legal obligation to report you to the county if they know you are using. If his stool does test positive I wouldn't be surprised if CPS does get involved. They may require you to take classes, submit to random drug testing and home visits. CPS ultimate goal is to keep children with their families provided its safe so they try to work with parents unless being there is a danger to the child. The best thing you can do is stay clean and jump through whatever hoops they ask you too. I'm not trying to scare you but these are possibilities. Its also possible he'll test negative and nothing will come of it.