I would go back to the vet & get more tests or get a 2nd opinion just in case as Amy said, it's something more serious although arthritis is serious pain in itself. Poor girl. I hope you can get the pain under control. 
Where does she sleep & what does she sleep on? If she's just sleeping on a hard floor, that wont be helping. She needs to be kept comfortable.
It's hard to talk about drugs because if you're in Singapore, you might have different treatments or the drugs might go under another name. I would be asking the vet about painkillers, anti-inflammatories & glucosamine. Cortisone (Prednisone) is a good anti-inflammatory but that's assuming it is arthritis.
Good luck & keep us posted re how she's progressing.
Where does she sleep & what does she sleep on? If she's just sleeping on a hard floor, that wont be helping. She needs to be kept comfortable.
It's hard to talk about drugs because if you're in Singapore, you might have different treatments or the drugs might go under another name. I would be asking the vet about painkillers, anti-inflammatories & glucosamine. Cortisone (Prednisone) is a good anti-inflammatory but that's assuming it is arthritis.
Good luck & keep us posted re how she's progressing.