I have irrational fear of death as well. I'm 23, and have felt this way ever since I was younger. Recently it's gotten better, but I haven't had a panic attack recently (just overall general anxiety is what I've been seeming to suffer from more).
When I got my first panic attack at the age of 18, I thought I was dying. Like the prior post, my left arm was going numb, reality seemed obsolete, etc. After that, the irrational fear of death came back into full force. I was always afraid of when my next one would strike. I sat in the back of the classroom incase it happened. I had to plan out all of my next steps in case it happened in public.
Whenever I felt a panic attack coming on, I found the best strategy was to distract myself from the overwhelming anxiousness, whether that be starting a conversation with someone, watching tv, distracting myself someone. I also was perscribed xanax after multiple attempts of seeing different doctors (I believe I had a hard time getting the script because I was only 19 at the time). The xanax provided me with a safety. It was a mental safety. It allowed me to know I could take one, in case I was in public, and it would provide me with a sense of calmness.
I haven't had one in a few years, but just have omnipresent anxiety instead. It's like I have a mixture of panic disorder and GAD. Best of both worlds (;
I would try medication, therapy, and have a back up plan of what you can do during these panic attacks (have someone you can call, etc).
Once you feel you have control, it will hopefully get better, and you won't feel it disables you, makes you give too much concentration on health so that you can spend it having great times with your kids (: