A Dream with Memories

I woke up today slightly disturbed by my dreams from the night before.  I didn't have a bad dream, on the contrary, it was quite a pleasant and peaceful dream.  What disturbs me is that, on awaking, I reflected on the dream itself. 

In the dream, I was taking care of my granddaughter (In reality, I do not have a granddaughter, only sons and grandsons) and we were getting ready to go outside. It had gotten quite chilly and my little granddaughter had only a little blue checked sundress with tennis shoes on.  I feared that this would not be enough to keep her warm.  It was at this time that my youngest son mentioned, "Hey, remember when we went shopping last week?  We bought a little blue sweater that should fit her just right!" 

Here's the disturbing part.  In my dream, I remembered (remembered!) vividly the shopping trip that I had taken a week ago.  On that shopping trip, I had bought a light blue sweater with tiny flowers sewn around the collar.  I had also bought a small toy that I had already given to my granddaughter!  All in all it had been a nice day of shopping.  Only problem is, I do not generally like to shop (in reality) and I have no little girls that I shop for, so where do these "memories" come from?

It really made me reflect on our current situation here in this "reality" we call our wakeful state.  We work, play, interact and have memories of those times.  
Sometimes, in my dreams, I do these same things.  I eat, play, work, hurt, laugh and cry and have friends and memories that are not real.  Which is reality and which is the dream?  (I understand that dreams and reality are different, I'm just asking a rhetorical question) I remember once hearing someone say that maybe, what we call life is actually just a dream in the mind of God.  How strange to think that maybe this world has no more substance than that of a dream world.  This leads me to wonder about the afterlife.  When we die, is there a part of us that continues on into another reality similar to our dreamstate or does this function die out along with our brain?  If so, then how can we account for the many accounts of life after death experiences that we have all heard where people have had dream-like/life-like things happen to them after the heart has stopped beating and brain activity cannot be seen?  Just another deep thought, of which I have many.