Hi Rachael, sorry you're dealing with so much...

Mine spread from L knee to L foot, then L thigh and rest of the leg, then jumped across to my R foot, then my L arm most recently. There's no rhyme or reason with CRPS.

Vitamin C is meant to help prevent spread, I know there is evidence that it reduces spread after surgery etc, and some take it to prevent spread generally. I don't know if it works like that, but it's only Vit C so might be worth a go.

I personally found Gabapentin did very little to help mine (docs love it because it is cheap to prescribe), I'm back on a low dose of Lyrica again now (more expensive for them) and coping better, but my arm is getting worse with the symptoms. Physio is really important, and that you get the meds to control your pain and let you do that. Hope you have a good GP who is supportive and ready to partner you through this

Take care and all the best.

Bram.