What could my dream mean?

I had a dream within a dream. In the first dream, I was aware that I was dreaming, and I was talking to an aunt and my mom. I was telling them everything I wanted to tell them because in the first dream I somehow knew I was dying. Then, there was a big twist at the end of the first one because it turned out I was actually dead already. I died in a car crash with a couple of friends. We were in a red, top-down sports car going around a bend. This was the start of the second dream, which I wasn't aware was a dream. I remember thinking that everything happening to me then was real, that I was really dead. After my death I was going around what looked like a vacation house my family lived in. I was trying to tell my mom to stop grieving but I couldn't. There was this big slab of rock on the patio that said I died on January 16. I also remember seeing my siblings and wanting to hold them so badly but I couldn't because I was dead. I woke up crying and my chest felt really constricted and heavy. What could this mean?