If the glands are full and the dog is scooting the glands MUST be emptied. You can do it yourself,
but it is best to have the vet show you how. Just the fact of her scooting indicates it is uncomfortable for her. You don't want to wait too long to get her to the vet because full anal glands can become inflamed and infected, which is
very uncomfortable, if not downright painful, for your dog. Worst case scenario, the anal glands can burst, and this will cause additional pain for your poor dog and pain for your poor wallet.
I've had dogs who never needed it done, dogs who needed it done occasionally, and one who needed it done
every three weeks. Of course, I'm older than dirt, so I've had a lot of dogs.
I preferred not to do it myself for my last dog, Hailey, because her anal glands were hard to reach, and I didn't want to hurt her. I have done it for other dogs, but I never felt comfortable that I was doing it correctly and that I was getting it all out. I remember some vet somewhere telling me if you don't get it all out, you can cause more problems.
Let us know what your vet says. If you're going to do this yourself after the vet teaches you how, invest in a box of disposable gloves, and be careful -- it can shoot out onto you, and has a mighty smell.