Kirsten, it has been the same here, 2 kittens running around and playing with each other. Then they stop and pant like dogs, and go and drink water. We asked this from our vet last time we went there and he said it's fine, it's the weather doing the tricks, it's so warm (well, it was, has cooled down here too, thank godness!), we just need to make sure they have fresh water available all the time.

Isn't it great to watch a energetic kitten playing?