For the past week or so i've had trouble breathing. it's as if something is pushing down on my lunge and stopping me from being able to breath in

See a doctor : At your age it may be anxiety or stress but cannot say for sure whether it may be a spontaneous issue, like a collapsed lung or arrhythmia? See your doctor who can decide based on your other medical history and examination if you'd need a chest X-ray, EKG, other tests. If issue is worsening then proceed to an emergency room. Good luck.