Thank you so much for helping me MrFlynn.
I did a FACTORY RESET
I went to the Sims 3 Store/ Purcahse History to re-download Dragon Valley (only): nothing happened.
I also tried to download Riverview: nothing happened, so it's not just Dragon Valley that is messed up.
I downloaded a new item (a shirt), it started to download just fine, but when I loaded the game it wasn't there, in fact there is nothing with the little bag symbol that means it comes from the shop.
I also went to SaltyPaws's topic, as MrsFlynn recommended, and went to the "Downloads Dashboard" and tried to download ONLY Dragon Valley from there and nothing happened, so I went back to the Downloads Dashboard and next to Dragon Valley I had a red note saying "Download Error". So lately I've been researching on this "Download Error"...
Important: I'm on MAC, OS X, 10.9.2 and the last thing I read was that this is an ongoing problem for us Mac users, I've found lots of really upset Sim players on Mac who have this same problem and don't know how to fix it...
I'll go do the last thing I always do: un-install everything and infall everything back. I don't know if it will help, since the problem is with the store items, but I'll see and I'll tell you how it went.