When I woke up this morning, Papi was very quiet laying down in her cage and this surprised me as she is the nosiest in the house and will bark very loud to wake everyone up. I carried her out and she started to cry when I put her down. There were no sign of injury at all but she just couldn't stand up. I tried helping her to get up so that I could wear diaper on her. At first I thought maybe the nails were causing the problem since they were a bit long, I trimmed them and the problem still the same. After a while I called the vet and ask his opinion and showed him the video above. He gave me some pain killer for Papi and I will see how it goes tomorrow. If there is no improvement on Papi after a few tablets, I will take her to the vet and do some thorough check up.