Wqnted To Get On Subutex After A Mishap

On wed of last week a friend of mine gave me subutex and neither of us knew that if I was taking methadose pills that I would go in to full blown withdrawl. Omg I wanted to die. Needless to say I had to take alot of H To get myself out of the withdrawl. So since wed night I have been back on H because I wanted to get of the methadose pills. So I wanted to take subutex for a few days to get off the H and be done with this whole crap but I didnt know when it would be safe to take it without having a repeat and going into withdrawl because of the methadose . So im asking how long should I wait to take the subutex ?
When I just started Suboxone the Dr. told me my system had to be clean for 1 week before hand or I would get very sick. I did it . And it worked .
Just want to be clear. When "I did it" I meant I staye clean .