Hey! i have been having a cold sensation in my left side in the heart area and some pains in my chest to what could the cause be?

Anxiety?: Heart disease at 18 is very unlikely. Most chest discomfort at that age is not serious. Anxiety is a common cause of chest discomfort. If chest discomfort happens mostly with exercise, or results in significant breathing trouble or severe dizziness, then it warrants medical investigation. If exercise is well-tolerated, then chest discomfort is typically not worrisome.