The Dink Network

I have a small room, which I tidy up by putting things back where they were, but it still is a very unhealthy place to spend my time. When I first moved in, there was a small patch of black dots on the ceiling that wouldn't come off. I thought nothing of it. Now six years later, and all of a sudden three patches have emerged, all of them having dots growing in density. Every morning when I wake up, their is always condensation near the patches too, but nowhere else. I guess it doesn't help i never open the blinds or windows, but it is winter in Tasmania, and I'm cold enough as it is with the windows closed.