In agony with my shoulder, doctor won't help

I've had a pain in my left shoulder, around the shoulder blade and down my left arm for about 3 months. It was very bad for the first 2 weeks then improved slowly. Every time I think it's on the mend it gets very sore again.
Yesterday was just awful. I woke up in agony. Couldn't get the pain to ease at all. Otc painkillers did nothing. So I went to the doctor yesterday afternoon and all she did was told me to go home and take some nurofen. That was it. The whole time i was in with the doctor i was crying because I was in so much pain. I can't believe she just left me like this. I'm in bits here. It's taken me a few hours to write this. Couldn't sleep last night from pain.
I'm truly sickened with the doctor. She wouldn't even prescribe me something stronger to help ease the pain. She won't send me for any scan. My husband and even my son think that the doctor was disgraceful with what she did.
What would any of you do now? I'm lying here in agony. Don't know what's causing it and I've nothing for the pain. Can't go to my doctor. I'm at a loss now. Any advice?

Could you see another doctor?

I went to a walk in clinic on Wednesday. I couldn't take the pain anymore.
The doctor there is sending me for an mri on my spine. She also gave me anti inflammatories and strong painkillers, which have helped a good bit.
I'm now waiting on a phonecall for the mri appointment. I'm still very sore but not crying and roaring in pain all the time.
And battling with my HA over this now.
I'm honestly sickened to my stomach with what the doctor did to me on Monday, when she saw the pain that I was clearly in. I don't know what she was playing at.

Sounds like tendonitis to me. Sorry to hear you have it! Take the anti inflammatory meds and go to a physical therapist. With the right treatment and exercise it will get better in 1 week and in 3-4 weeks it will be over. Good luck!