It is hard to give you an accurate diagnosis over the Internet without meeting you in person but I can give you some helpful pointers.
You are extremely young for developing a serious heart condition. In addition, you do not describe any significant risk factors that is history of high blood pressure, high cholesterol, diabetes, smoking, family history of premature heart disease.
With an absence of any risk factors and your age, it is very unlikely that you suffer from a heart condition.
chest pain or chest discomfort can arise due to multiple conditions like lung related problems or food pipe related problems or musculoskeletal issues.
Reading the description of your symptoms, I suspect that the latter two are the likely culprits in your case.
Regardless, if you continue to feel unwell, I suggest that you seek medical attention from your primary care doctor.
hope that helps
Used to smoke for 3 years, quit 7 months ago. Ive been.burping alot & my upper back hurts, feels as if it needs to be cracked... if I put my shoulders back it cracks.. If that helps?