I have sharp stomach pain that sometimes go up to my chest. I also am quite breathless and chest sometimes is tight. In only, 19?
Anxiety possible. You should certainly see your primary care doctor first, who may then refer you to a specialist to rule out any medical problems you may have. If no medical conditions are found you should be evaluated for underlying anxiety disorders. Anxiety disorders ate very common. Besides "worrying", anxiety can make you have all kinds of somatic complaints, including chest pain, shortness of breath etc.
May be Anxiety. It is unusual for a young person to have a heart attack. After you are checked out to be sure your heart is okay, you may need treatment for something called panic disorder. Do others in your family have similar spells? Do your spells occur out of the blue, or in response to certain situations? Panic attacks are common. You avoid medications which may be addictive, if you need medicine.
See your doctor. Important to rule out serious causes. Although, in a 19 year old these would be rare.