Postpartum depression

My family doesn’t believe I’m depressed. They keep blowing it off saying I’m just tired. My baby is up almost constantly and never sleeps at night. I’m 18, I have a 7 week old and I still love at home with my parents and siblings. I am so stressed and alone. I feel like I have no one. I don’t know what to do anymore. I don’t regret my baby but I’m really having a hard time. I cry at night and breakdown because I can’t handle it. I feel like I’m doing everything wrong. I take care of my baby alone mostly. About 97% I do myself. I also breastfeed. I keep randomly getting very anxious and overwhelmed (even when doing nothing) and I start panicking. I feel to embarrassed to talk to my doctor. And now I can’t talk to my family. They think I’m just tired and I need to get over it. They won’t help at all. I can’t tell my boyfriend or his family because I’m really embarrassed. Am I depressed or is this normal for a young first time mom?