I am 16 years old and this happens frequently and out of nowhere ?

Chest pain: Severe chest pains in adolescence almost never represent heart attacks or strokes. Pains that you describe that continue for an hour should be evaluated by a physician. Pains that last for several very painful minutes, sudden onset, and then are gone with or without NSAIDs, are much more common in adolescents. Suggest resting in a comfortable position, possibly with a warm compress.

Chest pain : Chest pain that is severe or last longer than 30 minutes or associated with lightheadedness shortness of breath passing out or irregular heartbeat or coughing up blood requires immediate medical attention and evaluation. Otherwise make an appointment with your primary care physician for in person evaluation of chest pain in the next week or two