depends on the person like always but yes, in my opinion, it should get you high. methadone doesnt block other opiates from working. its just adds to there effect when taken together. suboxone on the other hand, does block opiates from filling some of your brains opiate recepters......preventing you from getting high.
and in this situation...you took the heroin and oxy before you took the methadone, so you dont really have anything to worry about in the first place.
*just some added advice......This has already been discussed dozens of times allready here on BL so try using the search engine before starting a thread next time*