What Causes Pain Above The Elbow And Low BP?

hi doc.i m nityada.i m a college student in bangalore.i live in hostel.i do not get proper food here.and also i have pain in my left hand above elbow sometimes...my bp is 90/60...is it a cause of worry???coz i also fainted few days back...and feel unconcious sometimes..can you suggest a good amway medicine or any other medicine to recover from this problem..