Hi Heather. Poor you, I know what it feels like and I sympathise completely. I have also suffered a lot of pain in my neck and collar bone area and I hate to say that this is something which has also carried on after the MUA to some extent. I think that's because we have been using those muscles to lift the arm because the shoulder joint isn't doing the work. I had the same thing with my previous frozen shoulder too. This is slowly improving a bit but I still get bad days with my neck. I try to stretch it by tipping my head to one side to loosen the tension and I find that a microwaved wheat bag laid around my neck helps to relax it.
Comparing what you are feeling at the moment with the discomfort following an MUA I do still think it's worth having. It is now 5.5 weeks after my procedure and I am still not pain free, some days are worse than others for some reason. It's a different kind of pain though - certainly nowhere near as bad as the pain you feel when you jar your arm at the moment; like you, that made me feel sick for a minute or more.
I am still having the trigger point massage. I think my physio has been all over my shoulder, neck, upper and lower am and week by week there isn't an inch of muscle which hasn't felt like it's been hit with a hammer. I do think that when my muscles have finally lost the tension and waste products which have built up over the last months, and regained some proper strength, I will begin to feel much better. For me, it isn't a question of just having regained 75% of my movement back, it's more about feeling more comfortable and having my quality of life - and sleep - back again. I am beginning to feel that it isn't far off.
I go back to see the surgeon on 14th August and I'm hoping he will think that my recovery is normal. My physio says she isn't familiar enough with this procedure to know whether I should have full movement back by now. I definitely haven't got that yet but enough to do most things I need to do.
Good luck with getting your shoulder treated. I hope and pray that your other shoulder isn't going the same way.