She may have a spinal cord injury or pinched nerve, I'd get her to the vet ASAP. Best wishes.
My Pomeranian Started Panting & Hind Legs Are Stiff But She Cannot Walk Because They Fall Out From Under Her. What Could Be Wrong?
The same thing happens to my Rat Terrier. She has had this for about 1 year. My vet found a problem in her spinal cord in her neck area. She also told me she is very nervous and has panick attacks. Does your dog lay on its side when this happens? ...and does her body temperature feel hot? That's what happens to my dog. I don't know if it's the same condition, but hope this helps. Good luck.
I don't know but my dog has the same problem and the vet told me that it was the disk on her back after they did xray they told me that she might need surgery there might be a possibilty that she might get better .