postpartum depression??

I'm 4 weeks postpartum and I've been feeling really down. I keep reading online that PPD makes you feel distant from baby and I don't feel that way. I more or less feel like I'm not a good enough mother. I find myself crying a lot for no reason. Getting easily frustrated and upset, especially towards my SO. Some nights if the baby is really fussy and I can't get him to stop crying I just start crying. I just want to sleep all the time. Just wake up to feed, change and take care of baby's needs then go back to sleep if I could. I feel like my SO doesn't take how I feel seriously. He works nights and long hours so I'm alone a lot of the time. I just feel really alone. I just thought after having my baby it would be so magical and happy. And I am so happy to have him and grateful. It's just this weird mixture of I'm extremely happy but also weirdly sad. I feel almost detached from the world.