Thanks for choosing H.C.M. for query
By your query I came to know that you are feeling a lump in the throat after exercise, this discomfort increases as the day passes. You are also having tightness in chest though stress test
Since your stress test are normal and your problems are more marked in the evening hours while in morning you have nothing, This clearly indicates that here anxiety
is playing important role. Thus you are supposed to have anxiety induced gastritis
To confirm it and to manage it you should do-
1- Upper G.I. endoscopy
2- Complete cardiac examination and investigations.
Till you are waiting for meeting wiht specialist you may take-
2- Angiolytic drugs.
I hope this will help you.