Hi. Thanks for posting your query and for using Health Care Magic
Well you have two categories of symptoms
1. Burning sensation in stomach which is likely related to gastritis
. You are on multple medication which can contribute to this.
2. Palpitations, light headedness and shortness of breath
on exertion. You should get two tests to r/o cardiac involvement. One an ECHO and second a HOLTER. This will conclusively rule out any major cadriac problem and you can be reassured.
Hope this answers your query.
Do get back with reports for further information
Thanks and Regards