Sorry to hear of your situation and pain.
I am in no position to preach as a painkiller (codeine) addict myself. My experience with doctors, previously admitting to diazepam misuse has been very bad, and a note on my file was put that marks me out as a potential drug addict and I can’t get anything on prescription now. Your experience may vary – GPs are people and will all have their own prejudice.
I am not in Scotland, but I am trying to find independent help, from a charity or independent service – that way the doctors file will not haunt my future.
I hope things work out for you.
Things that really help with me:
Make sure I’m hydrated.
Take 5-HTP
Take vitamin B
Take exercise every day – even a walk is good.
Sleep as much as you can – but also make sure you get up when the alarm goes off.