So, today I went on Virtual Villagers and my person Zuna was 'worried about housing'. I scrolled around the village to see if any huts needed to be built, but there wasn't any. I don't know what this means. Can somebody please tell me?

You are getting rather too many villagers for the number of huts. You'll probably need to upgrade construction to a higher level to make the foundations of a new hut appear. Until a new hut is built your tribe won't be able to have any babies.

Ok. I think it was because I had reached my max population, since I was at level 3 construction already. I have never seen this action since.