I am not a psychiatrist and not trained whatsoever. All I can offer you is empathy and understanding.
I have had a very traumatic past as well. I am not willing to share it on this site or any, though. After having my son I experienced the same anxiety you are voicing. I was sure I was having brain aneurisms, heart attacks, things like that. If I got a strange flicker of light in my vision I would assume I was hallucinating. I would end up on the floor unable to breathe with severe tunnel vision - all caused by anxiety. I would get heart palpatations, from anxiety. My whole face would twitch for days on end.
It is an awful feeling, I remember that period of my life very well. I got out of it by accepting the fact I had some form of depression, and leaving my house. Getting out. I would lock myself in and never leave. So I made a radical life change by moving to a different city that I liked - and got my body healthy. After my body got healthier, so did my fears and pains from the past. As I got confident that all it was was anxiety, it passed. All the physical symptoms.
When you experience things as terrible as you have, there is no cure for that heartache. So I'm going to say what I wish others had said to me:
No, you are not going to die. You are a great person with strong will and you just need to keep on going. You will make it through this!
Also I found what helped my anxiety is if I wrote down my fears. Once I read them back I was able to rationalize and kind of saw how ridiculous my fears really were. If you get a chance, try and catch it early and jot down how you feel.
You are not alone! Just remember you ARE a survivor.