Thanks for providing more information.
As you have heart palpitations and chest tightness so you need to make a consultation with a Cardiologist and undergo EKG,Echocardiography,holter monitor,blood pressure monitoring,Chest X-ray and blood work like Lipid panel,CBC,ESR to rule out cardiac problem(Cardiac arrhythmia,Acute coronary syndrome).
Chest X-ray helps to detect lung problem however it is less likely.
You can try OTC Zantac to see if it provides relief from sensation like something stuck in yout throat,cough,tightness in chest.
Avoid late night work and eating.
Drink warm liquids and do saline gargles.
And i recommend to consult your family doctor before consulting either a cardiologist or pulmonary specialist.
Hope this helps.
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