<s>[INST] Hi, I am a 16 year old boy and have had a very healthy heart at every checkup. My cholestoral, blood pressure has been very good but just starting in August I have noticed my heart beating faster and I have been short of breath and very tired and sometimes dizzy. These symptoms happen every now and then and Ive been pretty stressed lately. I went to my regular doctor and he took blood and an EKG and found everything to be fine. It still occurs every once in a while and my whole body fills warm [/INST] Hi thereAfter going through your query I understand your concern.I would like to tell you that predominantly your symptoms are suggestive of anxiety disorder but as you are young so kindly get one echocardiography done to rule out any congenital heart disease.Hope to have been helpful.Kind Regards Dr Navneet Bansal </s>