I had a single injection of pethidine (or at least, I think it was just one) pushed on me by my midwife. As soon as I got to the hospital, she told me that she "likes to give it to everyone," and since it wasn't a name I was familiar with, I thought maybe it wasn't that bad, a kind of midwife secret. And she was horribly pressuring. I wasn't even feeling that bad, and was handling pain through breathing and tapping my toes (lol, that's how I handle pain).
It was awful. I went from energetic and my normal self, to loopy and out of control and not being able to open my eyes...and it had NO effect on how I felt the pain at all.
I ended up being put under for a c-section after five hours of pushing because of failure to progress, and the doctor later told me that he caused a lot of tearing on my uterus because the baby was difficult to get out, and because of that, he doesn't recommend a vaginal birth for me next time. (But that's really another topic for another thread.)
I really feel that circumstances could have been different had I not had the pethidine. Maybe it would have ended up the same, but at least I would have felt like I was making the decision to have a c-section myself, and that I could have been a better pusher if I had been not drugged up.
Like you, I didn't want an epidural because of my mother's urging, and I still don't think I'd want one, but if I wanted pain relief, I would choose a different route than pethidine because of my own personal experience. I will not go down that route again!
I would have much rathered that they gave me an epidural for pain relief and rest than just cut me open though.