Hello. Very Good morning. I think you should go for an E.C.G to Rule out any cardio-vascular disease. If the ECG is normal, and cardio disease is ruled out, then it must be " Costochondritis ",  which means inflammation of muscles & assosiated rib cage.  So in this case we have to get differential diagnosis. You must go for an E.C.G & measures your blood pressure along with blood glucose as a precaution, because you are now 40 years +. There is no need for chest x - RAY. After the report,  kindly come to practo chat for your treatment and satisfaction. Take care and good luck. Bye.