Mastitis ??

Ok so I barely had my baby 4 days ago

And my temperature is not high it's 98.3 it is going up tho earlier I was 97

But the thing is I'm having chills and like body ache as well as headache

Could this be mastitis or the beginning of it ?

Cause my breast are very engorged but the thing is there is no milk coming out at all they're just very hard and the pain is not too bad but I am in pain I've tried cabbage leaves and I don't see much difference

***my baby passed away due to anencephaly so that's why I'm not breastfeeding