agggh how to stop 3yo hitting/kicking

[nouveaupauvre]

my lovely gentle little boy has suddenly been replaced by a whirling dervish. all he wants to do is play rough and tumble games, which is fine, but he has also started kicking/hitting/headbutting when he doesn't get his own way about something - or, indeed, sometimes just to see what happens.
previously we've punished him by taking a toy away for bad behaviour which has worked but now that no longer seems to be enough. leaving him in his room alone for cooling down time seems to be the most effective thing but i suspect won't work for long.
what has anyone else tried? was thinking about star charts to reward days when there is no whacking but not sure if that's the right way to go. partly i think it's tiredness (he's just given up a daytime sleep and gets very tired by the end of the day) but there is an undercurrent of aggression that i find quite upsetting to deal with - it's not like he's lashing out in a tantrum. any thoughts?

hi i find my 3year old can be very much the same when he gets tired. i put him in a naughty step for three minutes ( his age) the go to him bend down to his level and explain to him that what he is doing is naughty and that it hurts mummy or whoever it is he has done it to. you just have to be persistant in what your doing and keep at it.

a child only has a small memory so punishing them long term isn't affective at this age, i don't feel anyway.

the star chart maybe a good idea as rewarding good behaiour may encourage him to behave more when he realises that been naughty won't get him anywhere. but my thoughts ae not always to reward him with toys or sweets but that he can pick what he has for tea that night or a trip out somewhere as you don't want him becoming spoilt and expecting because you have gone shopping and he has been good all week that he desevers a toy. hope this helps