PPD... IDK

So I just had my third and final baby 5 weeks ago, I am I feel lost. I am sure I had PPD with both my other kids, but I just dealt with it quietly and alone, but this time idk if I can. To add more to it CPS was called stating we hit my son, that's what he told someone, he says bc he wasn't getting attention from his teacher, we seriously don't hit our kids.. we have spanked in the past months ago, but didn't really change anything so we stopped and are doing different methods. Even when we were spanking it was not excessive or anything crazy. But that just adds to my depression, I feel so alone and just want to cry I have 0 friends or family seriously none, I came from a family of addicts and have nothing to do with anyone in my family. I just am lost I feel like a failure, I am stressed, tired can't think and I am hurt. I am hurt I feel like this when I have 3 amazing kids I gave life to, hurt that my fiance and I are being accused of something we didn't do, hurt I am feeling this way when I have a new baby who is so happy, when mommy sits answer cries. I just want things to be ok, CPS to go away, my son's anger and outbursts issues to stop, and me to be happy and feel happy, bc I should I was given the gift of chikdren and a man who loves me and I get to be a step mom to his kid, who is an amazing smart boy. Help. I just want to feel like it's all ok, like it'll all be ok.