<s>[INST] I am a 16 year old active female, earlier today i had a sudden onset of pain on my left side of my back between my shoulder blades, it felt like i was being stavged abd it would radiate to my chest And soon reached my left arm and shoulder. Within an hour the pain got up my neck making it difficult for me to even sit without pain. I took two ibiprophen and it helped with the pain but now its returning and im not sure what the cause of it is. I have no history of heart problems nor is it in my genes. [/INST] Hello,I had gone through the case and this is not related to cardiac. It might be muscular spasm or cervical spondylitis.So go for cervical X-ray and take mild pain killer and muscle relaxant gel with hot water bag massage. Do not use pillow for mean time.Hope my answer will be effective for you.Thanks </s>