I have had back pain/shoulder pain with both this pg and last. Last time round the only thing that stopped my 2-3 physio visit a week 'habit' for relief was to stop wearing bras and wear stretchy singlet tops instead.

Fortunately I'm only a b-c cup so I didn't need a lot of support so I could get away with wearing the singlet. It made all the difference and I literally stopped going to physio as soon as I stopped wearing a bra.

This time round I could feel the pain fairly early so stopped wearing a bra but still get shoulder pain. So depending whether I feel the need for support (I think I'm a bit bigger this time round) I migh wear a bra 2/3 times a week and cope with a stretch singlet top inbetween.

I hope you can find something to manage your discomfort.