Holy sh*t it hurts! Think its a trapped nerve

I can hardly move.
I had it with my first pregnancy but it was from about 29weeks and it was a lot worse. I'm a pretty tough person but I don't think I can handle this pain until I give birth.
I was at work earlier and I turned and I got a horrible stabbing pain and I yelped and everyone was staring and a few people came over to see if I was alright! That's how bad it is at times involuntary noises come out my mouth.
I've got my 23weeks scan tomorrow to see baby again cos it was being naughty last time and wouldn't keep still so I'll ask there.
Has anyone had one of those pregnancy massages? Maybe that would help!
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