Just feel 😞

I just feel so down at the moment, I am so grateful to be carrying my baby girl don't get me wrong but I feel like I'm just a bump now and no-one sees me as a person. I feel so detached from everything apart from her, I just want to cry all the time and I don't want to leave the house! I just look in the mirror and I don't see me anymore, it's just a blank stare looking back at me... Someone please help me with what 'this' is, I'm seeing my Doctor tomorrow.