Hello and thank you for using HCM.I carefully read your question and i understand your concern but don t worry. I will try to explain you something. First of all, you don t have to worry for your chest pains. This sharp, fulminate chest pains usually are not typical cardiac pains, they are just nerviness pains that come and go.You are to young to have cardiac chest pains.This unconformable heart beat might be from different reasons. It might be just an extra systolic extopic beat. These are electrical impulses generating from parts of the heart different of that of normal sinus rhythm.These gives you the sensation of an skipped beat, you feel this chest discomfort and like all your body is beating and you experience this difficulties in breathing deeply . Sometimes this are quite normal at your age, they come and go. Sometimes they might be because of emotional stress or patologies like anemia, hyperthyroidism. So, as they are interfering in your daily live, my opinion as a cardiologist is that you might do a simple chek up. It is advisable to do a blood analyses, an electrocardiogram, echo-cardiography and a holter monitoring to see what kind of rhythm issue is this. At mean time avoid caffeine products and begin exercise training because this healps in reducing this heart beats even making them disappear at your age. Hope I was helpfull. BEST REGARDS