Sleeping problem

Hi..my girl is 3 wks old and she get cranky when she want to sleep. I am breastfeeding + top up formula milk (coz not enough supply). But i cannot calm her when she is cranky coz she want to be nurse when i carry her, even when she is already full. I am getting very stress up coz my confinement nanny is going off soon and i cannot calm my baby...anyone have such issue and how to resolve it?