What should I do now? I'm convinced I'm dieing..... PLEASE REPLY I NEED HELP?

You are the same way i am i have chest pains to and then i start worrying and it makes it worse and i freak out thinking i am dying but i am not i know it sucks big time but dont worry it will be ok i mean you had your heart watched and it came back normal so your heart is fine its form having Anxierty and it does that i have anxiety really bad and it runs my life i cant do anything because i start freaking out i hate it and wish i didnt have it go look up the signs of anxiety and will read thats wats going on with you i am sorry you have this to i know how you feel and i hope you learn to control it because it sucks i am sorry :[