Your symptoms are more towards a muscle strain or gas formation . But it's better we rule out cardiac cause , because at 45 years it's better to be cautious about cardiac reasons.
Just brufen will not help you much. Better to start on a muscle relaxant as well
Next Steps
kindly take an ECG - just to rule out.
give rest to the painful region.
Health Tips
do not ignore to take ECG , if you have associated palpitation , sweating