You wrote: "When I die I am quite sure it will be exactly like this concussion..."

Do you actually know what it is like to die or is your idea based on what you have read and learned? What course have you taken other than an intellectual one to prove or disprove what you are saying? Belief can be based on religion, science, or something else, but to believe is to not know yet accept the belief as truth.

Since I am not dead I do not know what will happen to me. Of course I know that the body will decay and disappear, but beyond this I do not know anything else about what happens to the essence of me. This is the best I can say on the matter: I simply do not know.

Having spent nearly 70 years enquiring into what I am beyond this body I have come across many startling realizations that are not part of scientific theory or discovery; nor are they part of religious dogma. They are borne of personal observation and experience. In fact, though science is great and useful, it cannot answer questions about many things that we all accept as true. For example, science cannot prove how you know you exist. And it cannot prove what it feels like to be alive, full of joy, depressed, and so on. It can offer some insight into physiological occurrences that correlate with the emotional/mental experiences, but the effect is not the cause: Post hot ergo propter hoc. Just a couple of example.

To speak with such certainty about a reality without having any real proof about what happens is your prerogative, but it doesn't make it any more of a fact.