Yes, there are bunch of people seeing spider when they wake up(there's a thread about this in DreamViews, I believe it's in Sleep and Health), I'm very interested why this happens, but I can't find scientific explanation =[
You said you felt buzzing sensation when you "died"--I wonder if it feels like that when you really die, cos I heard someone says sleep paralysis is when your are not fully in your body(not scientifically proved), and maybe your brain was trying to imitate the dying sensation?