Yes, actually I did have a brief memory of the afterlife once. In one dream I first had a past life memory in which I experienced how I died and after that the dream continued with me finding myself in the astral world or in the afterlife.
I was flying over a beautiful, golden beach and a turquoise and blue coloured sea. I don’t remember having any body or form, it seemed to me like I was a shapeless spirit being or just consciousness travelling through the air. I went down right to the spot where the waves met the shore. It was very peaceful, and I felt one with the surroundings, totally safe and free. The picture in my profile is inspired by this memory.
Then the scene shifted to another place which was like a park or garden. I had my human body from said past life again, but I was aware that I had died and that I was on the other side now. I experienced painfully how my death had affected another person close to me and it also became fully aware to me that my life had just been cut short. Not a very pleasant feeling, and I guess I just needed to go through the pain for once. There was also some symbolism involved during this scene which seemed very clear to me, but maybe wouldn’t be obvious to anyone else.
I woke up after this. Everything I experienced in this dream made total sense to me. Seashores and water in general always had a deep meaning to me. A beach like this would be exactly the place I would go to first after death to recover if I could choose.
Most of my past life memories came to me in dreams, mostly spontaneously. This was surely one of the most remarkable ones and the only one that would include something from the afterlife. It was part of a series of dreams and memories from different past lives I had at that time, but it wasn’t like the beginning of everything.
Btw, the death I remembered right before this was also one of being assassinated. Actually, I wanted to post something about this in your other thread because I can also relate to what you wrote about it there. I hope to get back to you soon.
From what I read on here, past life memories tend to occur in phases for many people. There are times with many memories in a rapid succession and then there are times with none. It was the same with me. So, enjoy the ride

and I would advice you to write down everything you remember now in a diary before you possibly forget some of the details later on.