You describe 'sore' chest, brought on by effort and relieved by rest. This must be viewed and investigated as heart pain, unless proved otherwise.
Is your BP controlled?
Have you tested you cholesterol?
You must SEE A CARDIOLOGIST AS SOON AS POSSIBLE. You need ECG and blood tests. If they are normal, you must do TMT (exercise ECG), ECHOcardiogram
and so on - until the diagnosis is ruled in or ruled out.
and others are not related to this and need a separate approach - Possibly Irritable Bowel syndrome? But that is not urgent