Will I ever be happy again?

My baby is 5 days old and it feels like it's been years. I'm so sleep deprived and stressed and anxious and depressed. I feel so detached from everything. I just want it to end. I find myself wishing that she was already months old. I got put on Zoloft so I'm hoping it works. I just want to feel better. I feel like I can't take care of my baby because I'm just not happy. :( I never want to feed her or do anything.