Well a cat twitching it's tail is very normal and it could mean different things, it may mean that the cat is happy, mad, or content, it all depends on what angle the tail is.
Well it was light twitching so I'm uncertain after watching other cats having seizures online. Compared to the ones online mine was just slight twitching. Is it still seizures or is it a different cause.
Well there are some flea sprays that may work. Also I heard that if your cat is playing to rough, you should put the kitten into a room and put some toys in there to let him let loose of his energy, it should be better after five or so minutes.