She may have hurt herself jumping off your bed, I rescued a yorkie and I had to train her to use the stairs I got for her, I would use boiled chicken and put it on the steps, she learned quick if she wanted all the chicken she'd have to climb to get it, now she's a little speed demon up & down the stairs. I know she hurt herself a few times jumping off the bed. As for the joints I would give her glucosamine for dogs, you can find that at any pet store, I hope I've helped a little...

Smaller dogs are most inclined to live longer than larger dogs but at seven she's starting to mature and to see her slow a tad wouldn't be uncommon (IMO). I have to agree that she may have injured herself jumping, maybe she didn't break anything but dogs can injure their muscle tissues just like people. I wouldn't encourage her to jump, but as Christine suggests start to bribe her up the stairs or lift her instead.

How thorough was the vet's exam? Did he run any blood tests and did he check her back and legs for any sensitivity? Next question: is she overweight?

Here is a link with info on the Corgi...I assume you have a Pembroke. Based on the info your gal is middle aged but as a breed they are prone to back problems. Your vet needs to check her back and in the near future she may need some x-rays to check her back and/or legs. Jumping, climbing stairs and maybe even walking up a ramp may be too painful if her back is the problem.

There are many supplements that help with joint problems and an OTC recommended by my vet is Cosequin DS. Not sure why your vet wants to wait until October to start her on anything.