Hind Motion Sensor My Dog Is Dragging Her Hind Legs!! She Was Healthy A Few Days Ago And It Came Up All Of The Sudden!?

My dog is dragging her hind legs!! She was healthy a few days ago and it came up all of the sudden!? - hind motion sensor

I read that the most likely cause is broken a disc in the spine. This could very well be because the pants are worried when massaging the lower back. There are no markings on the outside, so it's more likely something internal. She is very nervous, just walk on the 2 front legs and a lot of panting. Is there anything I can do without to a vet. (They are so expensive!) I've read that the therapeutic effect movement of the legs in a circular motion several times, could cure 4 minutes per day, the nerves in the spine. Suggestions or ideas? I want to really get serious answers. I am very worried.
She was healthy before 3 days and suddenly limping, walking slowly and was then drag the hind legs.

Thanks in advance!