No, we're going to talk about dreaming. Psychologists are slowly coming to a consensus that dreaming in general is a fairly random thing. What happens in your brain as you dream is that your neurons - the things your brain's made up of and what makes you work - basically just let off electrical charges in a random-ish way. I say random-ish because it's not precisely random, mathematically speaking, and it's theorised that there's a higher chance of neurons that have been fairly recently active have a higher chance of firing. This last bit is important.
Your brainbits talk to one another via electrical firing from neuron-to-neuron - your language centre, your muscle control centre, the bits where your vision is processed and sent on for translation into meaning. Not only that, but processing in these brainbits themselves are also conducted by neurons firing electricity in the form of chemical shit at one another. Now imagine that, because of how electricity conductors work, and chemicals, too, these things are kinda excitable and ready to go again once they've recovered a bit. This is the state your brain is in when you're asleep. Yeah, you've got some really weird (and cool) systems to stop you from suddenly going for a jog while you're dreaming (although as we know these things aren't always effective - I'm looking at you, sleepwalkers), but by and large, it's mostly your noggin going off and doing its own thing for a bit based on what you've done that day.
Which is why you're likely to dream about 1) stuff that's preying on your mind, and/or 2) completely bizarre shit. It's also why your dreams don't really matter at all, in all likelihood, and furthermore why no-one actually gives a shit about what you dreamt about.
Because in the end, dreaming is mostly just your brain farting in your sleep.