when you're asleep and just think about death, the fact that you, everyone you love, all you know will be dead, and in the future you'll be forgotten...
(Also for some reason when I do that I have a long think of God, if I should be a theist or an atheist )
when guests come over and you're in the room with your 'age group' while you are in one corner whilst everyone else is laughing and having fun in the other corner so you go but you don't actually understand what they say at all