Normal ekg, chest xray and d dimer. also had heart ultrasound come back normal about a year ago. does this mean i have a slim chance of a heart attack?

Loaded questions: Honestly your normal results from last year are kind of like a snapshot. We need a panoramic picture - are you a healthy weight? Do you exercise regularly? Do you smoke? Do you eat a healthy diet? What is your family history in regards to cardiac disease (genetics)? What is your cholesterol panel? All I can say about your tests is that one year ago you had a normal EKG/chest X-ray/ECHO/d-dimer

NO: At your age the change of a MI is highly unlikely, thought not unheard of, More definitive tests are an exercise Stress test or CT angio of the heart / lungs. The gold standard is a Cardiac Angio but at your age totally uncalled for

Heart risk factors: Now risk is low, but heart attack risk is low in menstruating females without obesity, familial lipid disorders, autoimmune disease,coagulation issues Marfan's,cocaine or amphetamine use. To maintain a low risk, keep a healthy weight,normal BP, avoid fatty foods, lots of sugars/ junk food/salt, avoid smoking, eat vegetables/fish, exercise, keep hydrated with water and liquids with electrolytes