Yeah man, although opioids constipate you, they definitely can give you some pretty massive gas. One of the reasons that opiates have always been very appealing to me is their constipatory (not a word, i know) properties. I have IBS to begin with, so when I'm using opiates I actually have the bowel functions of a normal human being. Instead of a dozen runny shits a day (which i experience sober, eating healthy etc.) i get a nice solid morning BM while on opiates. Fucked up existence of mine. Your gaseous functions, on the other hand, are completely normal for the amount of opioids you've been consuming. And i'll reiterate what some previous posters have said, if it's scaring you how fast your tolerance is going up, now is the time to stop, or at least take a break. It's all downhill from here.