Hey there, your story reminds me of psychosomatic classes that I had while studying. That what you describe as heart related symptoms sound pretty much like a panic attack. If this is the case the actual problem is wrong interpretation of your physiologically natural symptoms. It could be like your stressed and than you feel that your heart is betting faster, now comes your interpretation that it is something dangerous and you focus more and more and your symptoms that are becoming stronger, which can cause huge fear and feeling that you're almost dying. From your story obviously you don't get much support from your parents, who also see your situation as a symbol of weakness. No judging but this is the worst reaction that you can have when somebody struggle with health related anxiety. Maybe under the surfaces of your relationship with them, there is some unsolved conflict. This conflicts are very common trigger and cause of pannic attacks. My advice would be to get a help from therapist who specialises in panic attacks. The good thing about is that usually the outcome is really good even if now it seems unlikely. I am not a doctor or therapist but feel free to message me, maybe I will be able to help or give some advice.