I usually start my sims out as YAs, but I have noticed this a little bit too. I don't think it's a bug (unless its excessive in your case), I think it's just EA's interpretation of getting older. Everything starts to droop A little too much between YA and A, in my opinion. I would really like a way for my sims to age a bit more gracefully. Less hollowing of cheeks, and no mouth droopage. I don't know why EA made it like that, I mean YAs and As in Sims 2 looked pretty much the same. Another thing I have noticed, is that As have duller skin than YAs. This applies to both vanilla skin and custom skin. I don't like it.

She didn't get inside the house, that was the problem 

I've already figured out that I had to click a space near my Sim and have her "Swipe Something", but I was just wondering if there was some way to get her inside an unoccupied house. I guess not, it seems.

I have a quick question. I was playing a klepto, and I tried to have her steal from a house that was unoccupied, but it didn't work. Can kleptos only steal from houses that are occupied by other Sims?