Is he a crowntail?
My one young crowntail has been twitching for a couple of days when i have watched him. He seems to move quickly from one end of the tank to another or stops in mid stream twitches and turns back, It almost looks like a cat who has a flea on its back and gets irritated by it yes???
Anyway he seems fine today.... Maybe your betta is just feeling a bit frisky..lol