I'm struggling

I was diagnosed with depression right before I found out I was pregnant. Throughout my entire pregnancy I was battling with my depression without anyone knowing how bad it actually is. At the end of my pregnancy it started to get too much to handle on my own so I reached out to my mom. We brought it up to my doctor and they prescribed me some pills to help and to hopefully get a head start on post partum depression....its not working. It's been 3 weeks since I've given birth and it's been so hard. I have no help, I am so tired, and I just want to give up. I get so frustrated and overwhelmed when she cries and I cant figure out what's wrong with her. I feel like I cant tell anyone close to me that I need help. Im starting to resent my baby. I know it's not her fault, but I feel like I can't stop these feelings and I feel like a horrible mom. How do I stop these feelings? How do I beat this depression?