Hi there ~
Panic attacks are very common and a sense of "doom and gloom" or what you experience as a fear of dying is very common. Anxiety
that you are going to have a heart attack
and die are also common. They are also fearful of having such thoughts at night and do not get enough sleep. Gastritis
may worsen with this condition as stress and gastritis as well as hypertension
are related. Seeing a good psychiatrist
who can take care of your medications is helpful. I recommend that you do so at the earliest.
Take care and have a nice day !