When I switched from methadone to Sub it took 7-8 days to feel better. I quit the sub program first time because I thought that it didn't work. I just didn't wait long enough. Hang in there, it'll work. I don't mean to add any gloom to your situation but if I had it to do over i'd have just suffered the withdrawals the hydro-oxycodone. They suck. They suck hard, but they're over a lot quicker than methadone or suboxone withdrawal. As I am on day 10 of Sub withdrawal I must say that it doesn't suck quit as much as coming off of the other opiates. Don't get me wrong, it still hurts but it's a bit more tolerable.
Good luck my man