I dropped my camera now it won't save images to my SD card

I own a Nikon D5000 camera that I've had for a few months but recently I came home to find my camera on the floor with the lens completely detached. I think the cat knocked it off the countertop. The lens lost its attachment tabs but I don't care about that I have other lenses. The problem is when I take a picture it only shows me the last image taken before the camera fell. It won't save any new images. I don't see how this could be a bad SD card because how can an SD card break in a fall? I even formatted it and it still won't save images.

If you need the camera for your job which means that you should know that the camera needs to be sent in for repairs after it's been dropped.

The camera had suffered some internal damage after it's been dropped.
Plus why wasn't the camera sitting in the camera bag during the time that the camera wasn't in use?

Make sure the Lock on the SD card it not set to the Lock position.
If the Lock is on the card will not let the camera put pictures on it.
Try another card. Memory cards can be quite breakable.
If that does not work it is time to send it to Nikon for repairs.
The camera fell pretty hard so it may just be broke.
Because the lens got broke right off the of camera I think the camera is broke.

You now have a $450 paperweight.

You knew how inquisitive cats are and yet you didn't secure your camera. You knew about the fall and yet you fail to accept that the camera is also damaged. What's next? You don't know where to bring the camera for repairs? Bring it back to the store you bought it from. Warranty won't apply to product abuse though so prepare to pay for service and parts then decide which is more important to you, the camera and your job or the cat.