Back pain now moved to shoulder blade

[schroeder]

Am in quite a bit of pain to be frank.

I bent over a few weeks ago and pulled something in my back I think. Anyway it was my lower back and it has improved a bit.

However my shoulder blade absolutely kills me now; it gets worse as the day goes on to the point where after 6pm just lifting a cup of tea is painful.

I'm gonna have to make a gp appointment tomorrow I know.

Does anyone have any advice on what I can do until then?

I have taken ibuprofen, I've got a hot water bottle and there is

Do you spend a lot of time on MN sitting at a computer? That could be part of the problem.
Or (don't wish to be rude here) do you drink quite a bit of wine and have you been doing so for some years? If so it's possible your liver could be complaining, if you are No Longer Young.
I am not a doctor by the way and it might well just be that you sprained something. Hope the pain eases soon.

Seems muscular to me, as it gets worse the more I use it and gets better with rest. (also not doctor)

You could be yielding to the lower back pain and putting strain on the muscles in your upper back [quite regularly happens with my lower back injury]
Have you seen your GP he can give stronger muscle relaxants and pain killers that might help. Muscle damage is usually 6 weeks in healing
If it persists see your GP and ask for physio/exercises to do.
Feel better soon