First of all, please get a physical examination done to understand the cause of getting unconscious. I understand your fear of death. It can be quite paralysing. A lot of people are afraid of death and dying or even the thought of death. It’s not uncommon. Try to find out the root cause for this fear and then you will be able to see the concept of death in a different light. Death need not be feared. It is the fear of losing what you currently have that is making it difficult for you. Not death in itself. So learn to let go and accept that everything in life has a cycle of beginning and end. However, if this fear persists, please get a psychological evaluation done, post which therapy can do wonders for you.