Last night I had a dream that I was in what I thought was my house, but it was completely different. It still seemed familiar and completely normal, even though my sister was tied up in a tree in the jungle in the middle of the kitchen. My point is anything could seem familiar in a dream, even if you've never been there or it doesn't even exist. At least that's how it works for me. That's probably why it's hard for me to know when I'm dreaming.