I relapsed after 2 months, and had an ungodly tolerance to opiates. 60mg of IR oxy nearly killed me. It was the most hardcore nod I ever experienced, couldn't keep track of where I was nodded all over the place, lasted 12 hours too from oxy that is ridiculous. Only time in 5 years of railing heroin and taking any opiate/opioid I could get my hands on and this was the one and only time that afterwards I sensed and knew that I was on the brink of dying alone in a basement, not even knowing my name. And that dose when I was dependent might hold me over for the morning just barely I'd still be miserable with that... more like triple or quadruple that dose would have been okay for a few hours after 5 years of abuse. It was the best high I ever got out of this family of drugs though, but so not worth it and it led to a 2 week relapse about a week later that I am still recovering from 5 days later.
Your dose is way too high. I nearly fuckin died off 60mg man as a long term user, mixed with a valium though but still. Start with 10mg, 15mg max.