Hi my cat had 3 kittens on Sunday but seems very unsettled what should I do

Not enough information, melanie, just finish your post and let us know what is going on. She is probably unsettled because there are still more babies to be born. The 'queens' may not have all kittens at the same time. You must leave her completely alone and the kittens too. Let her do your job, and don't worry.