Thanks for your question on Health Care Magic. I can understand your situation and problem. In my opinion, we should first rule out heart related diseases because they are common cause for left sided chest pain with left arm numbness. So first get done ecg and 2d echo. If both are normal then no need to worry for heart diseases. Possibility of musculoskeletal pain is more in your case. So avoid movements causing pain. Avoid bad postures in sleep. Avoid heavyweight lifting and strenuous exercise like. Take painkiller and muscle relaxant drugs. Apply warm water pad on affected areas. Don t worry, you will be alright. Hope I have solved your query. Wish you good health. Thanks.