My partner does nothing.

Hi girls, so my newborn was undiagnosed Down syndrome born a week ago, I breastfeed her and thats going perfectly! But what I loose my shit at is my partner does literally nothing... I have a 2 almost 3 year old son aswell. I feel so burnt out during the end of the day because I’m the one feeding the baby, cleaning, cleaning after my son and everyone else, doing washing, changing my baby. I asked him to change the sheets but the baby shat on them and he did a half assed job and I ended up doing it. It just stresses me the out so much 😭 I’d rather not even have him here tbh. I’m so tired and have to do everything...