What Could Be The Reason For Underlying Cause Of Pain, Numbness And Swelling After A Failed IV Attempt In Arm?

I had a failed IV attempt 3 weeks ago and the pain in my arm and numbness in fingers are becoming unbearable. Have had ultrasound to r/o clot. percocet and ultram do not take care of pain. It is most severe in upper arm radiating across upper back and neck. Large hematoma has since gone away but no relief from pain. Being sent to PT in 3 days but no doctor has bothered to find out if it's a pinched nerve, a vascular problem or something else. Totally disgusted with my doctor. I think they belive it's a regular old sore arm and blow me off. Is PT a good idea when you don't know the underlying cause of pain, numbness and swelling. Pain is nauseating and constant. Thank you