Postpartum after an adoption

Is this normal to have postpartum depression after an adoption and a little bit of regret. I know I made the right decision. I was in no place to have a baby. My baby daddy OD'd on heroine and died. I am actually homeless and couch hoping. I found amazing parents for my baby. They were actually a lesbian couple and they were really nice to me. They asked me if I needed anything and I wish I had taken their help. I lied about how bad my situation was. I'm living in my car rn since I don't have a couch to hop on at the moment. I'm super depressed. I feel like that's where my regret is coming from because I know I can't have a baby living here. I'm a week postpartum and in so much pain... Physically and emotionally and I miss the baby. I know I gave my little boy an amazing chance with amazing parents. I just wish things would have turned out different so I could have kept him. I wonder if one day he will ask about me? I hope he understands I didn't do what I did because I didn't love him. This is the lowest I've felt in my whole life...