My forearm has been hurting since I got the flu shot last November. Is this normal?

I had Naproxen 500MG twice a day, it's too strong I stopped because of the red blood in the stool. I tried tylenol, hot and cold, cream. The throbbing in my arm up to my left shoulder has diminished but I still feel the pain in my forearm. The doctor told me that if it continues it will take an infiltration. There is no swelling or redness in the forearm. Thank you

thank you the doctor did not give me any diagnosis during my visit.