This is really the wrong forum for this, but let me offer advice as a person who has used opiate analgesics
for a long time, and has experience with
methadone.
Methadone is an effective pain medication, but is also used to treat opiate addiction. It has a very long half-life, which means that it stays in your body for a long time -- anywhere from 48-100 hours after dosing. This is one reason it is so difficult to withdraw from methadone.