Yep. You don't really get high if you are in pain.
I was prescribed oxy for 3 months following some major facial trauma (assault). Shattered zygomatic arch, stitches in my eyelid, torn ocular muscles. It hurt to look at things.
I actually got in the habit of keeping my good eye straight and turning my head to look at things, because if I just moved my eye, the other would follow under the bandages and feel like someone was driving a nail into it. The Oxy just took the edge off. Made the nail feel more like a thumb. I never felt euphoria. Sometimes though, I would lay in bed, get up, clean my apartment, then twitch and find that I was still laying in bed, hallucinating that I had spent an hour cleaning.
I remember taking 2 hours to poop a few times, at one point I strained too hard and my eye socket started bleeding.... Horrifying. Those are the situations these drugs are for. That is the kind of trauma that they are meant to protect you from feeling.
I tried some Hydromorphone and Oxy a couple years later. That gave me perspective on how fucked up I had been. I felt totally peaceful. I remember being at a party and just sitting in an armchair, watching what was going on through my eyelids. My eyes were closed, but I could swear that I was completely aware of everything going on, like I could see the entire room. I felt good and I was talking with people and they would occasionally ask me if I was passing out, but nope! I was fully aware, but looked asleep. Never really did the stuff again after that. I always thought weed was more of a "fun" thing to do with people.
Funny thing now is that Im prescribed adderall for ADHD. Sometimes I get the euphoria, but I actually feel the best when Im getting things dome that used to lose my interest, or force me to avoid them. If I finish reading a chapter in my textbooks in under 2 hours, I get a rush, maybe its a little bit from the amphetamines, but mostly its from being esthetic that it usually took me days of forcing myself to do the same amount of work.
These drugs are powerful. Anyone taking them needs to be very aware of how they affect them and know why they are taking them. Ive had many friends move up the hydro, oxy, methadone, heroine tree. Just like Ive had friends move up the coke, amphetamine, meth tree. They're both very, very bad ways to go and the underlying theme is always some sort of depression or mental issue they are self medicating.
IF you don't know why you're doing these drugs and/or you refuse to address the root cause of wanting to get high more than every now and then for kicks, they will consume you.
Sorry. Thats my rant/speculation. Had a friend OD and die on Heroin a few days ago, so I've been thinking about this pretty hard lately.