Hi there ~
I understand your concerns. Smoking methadone
along with weed may manifest as a set of symptoms that are very variable. It probably will show up on the swab test for saliva if you have smoked meth recently (within 1-2 days) or marijuana within about 2-3 months. I also believe that the urine tox screen or the serum tox screen are the more appropriate tests for making sure about a persons usage of substances. I also recommend that you consult a substance abuse
speciality trained psychiatrist
since you also have problems with oxycontin
as well as methadone with xanax. I hope you do so as soon as possible. Being on methadone to get off of oxycontin will be explained in detailed at a methadone clinic where you probably will get a referral from a psychiatrist's office.
I hope this helps. Take care and have a lovely day!