that doesn't go away- that happened to me with scamp when he was a kitten and it turned out he'd broken his leg way up by the shoulder. He acted normally except for the limp. Has a pin now- I brought him to vet after a week of limping. He's fine of course so not to worry if you wait it out a few days - well at least with scamp! I don't want to say it's ok to wait in case it isn't! It's so hard to do foster care................So hard..........