Pupa is having the worse of days. She was limping this morning, was very distressed which showed in her absolute calmness and wide opened eyes so I immediately called the only vet here that I trust. He said to give her 1/4 of an Aspirin 100 as he is almost sure it is thrombosis and the clot needed to be dissolved as soon as possible. I took her to see him straight away and unfortunately he was right. He checked her up, we took some x-rays (I helped wearing protection as I didn't want him to sedate her and she did so well!) and that showed no injuries. To be really sure, as finding the clot on x-ray or even CT is close to impossible, he clipped her claw and part of the skin, where she should have bled immediately and abundantly, but only after he squeezed the paw a drop of blood came out. So he could confirm his diagnosis. She is on Aspirin now and two kinds of other medicine. She is doing better, she has poor use of the left hind paw (she did run away from me promptly though :) ). I did some research on the Internet and I found out this is very painful and not many cats are lucky to recuperate after an occurrence like this. I really hope my Pupa is one of the lucky ones as only one leg seems to be affected. I took some days off work to be with her as I cannot be at work and worry about her all the time. I am sure some purrs and prayers will make a difference.