Hypochondriac, PTSD, Graves disease, and terrible anxiety

My spiral downward began at the age of 11 (I'm 42 now) at Disney World when I experienced my very first panic attack. Since then I have lived a life of fear of dying from a heart attack. My PTSD comes from a irresponsible doctor who almost killed me at the age of 29. I went in the hospital for a routine hysterectomy and landed in ICU for 2 days along with my husband and children being called in to say I wont make it through the night and prayers for my life with a hospital chaplain. To explain in a short way. he nicked a main artery and i almost bled to death in surgery. Now I wont go to the doctor because i'm scared he will find something wrong and want me hospitalized. I also have graves disease. It can typically cause severe anxiety. i am medicated for it although I make myself go to the doctor yearly to get my meds renewed. 2 DAYS BEFORE i GO FOR THE MED RECHECK i BEGIN THE FREAK OUT PROCESS AND GET ALL WORKED UP. I need to go to the dr for regular check ups at my age but cant. Im scared to death of dr's. I hyperventilate on a daily basis of fears and anxiety. i help take care of my elderly grandparent who are not well, my husband is facing a job change and we are set for another move. 3rd in 2 yrs now. I recently became an empty nester, my son is in the military and facing Afghanistan, Every time someone around me is sick I think I have the same thing. My biggest fear with this is a heart attack. If I even hear the word I immediately cant breathe and can even make myself think i'm having one. I feel overwhelmed. No suicide thoughts (I'm scared of dying) but feel I cant function on a daily basis. I take Zoloft daily and have for 15 yrs. (a good doctor diagnosed my with panic and anxiety way back in the day). I can go into public and around friends and be completely normal. At home its a different story. People would be shocked if they knew the truth about me. What should i do? I think I need help. Do I call a Psychiatrist? Do I need counseling? I want my life back. I want to be normal. I'm 42 yrs old. My kids are grown and I have a happy marriage. I should be having the time of my life but i'm not. Help!!!!