Suggest Treatment For Pain And Numbness In Fingers And Shoulder

Since 8th of march I am in terriblle pain. I can not really say where it is coming from - I can feel it on my back, shoulder, all the way down the left arm. I have two numb fingers - middle one and the one next to the thumb. Neither biceps or triceps are working like they should. The arm is weak, muscles are also painful. Usually I can feel the pain in middle arm area - I feel like these muscles are related to fingers that are numb. My GP put me on tramadol 50mg capsules and diclofenac. I asked for spinal x-ray, MRI or CT cause I suspect pinched nerve in cervical area of the spine. GP said that before any further examination, a physioterapist must see me. Is it right course of action? If it is pinched nerve, probably my muscles already started to degenerate. I am afraid. Please tell me what you think...