Arm pain related query. Investigations?

Hello doc, am non diabetic and non hypertensive  and am having anxiety. Am having following symptoms: 1. Left upper back pain 2. Left arm, forearm, elbow and wrist dull pain  when am rest 3. Am feeling pain in left breastbone area when am moving sides when am rest 4. Am not having chest pain while doing cardio workout 5. Sometimes am feeling lightheaded Investigations done before: 1. Tmt one and half year back normal 2. Echo normal 3. Recent ecg normal 4. I also consulted orthopedic he told mechanical pain Queries: 1. Is it anything related to heart??? 2. Is it angina ??? Stable or unstable??? 3. Is it cervical problem??? 4. Is it costochondritis??? Do I need any further investigations??? Please help...