young mom feeling lost

I had just turned twenty and my baby was born a month after. The pregnancy wasn't planned and it was a big shock for me. My boyfriend and I (and the baby now) live with his parents. It's great to have help with laundry, cooking, bathing the baby and stuff. But they don't let me take any decisions concerning the baby and get offended when I (politely) disagree with some of the stuff they do to my son, such as overheating him with too many blankets when it's warm outside, or letting him sleep on a not flat, soft surface. I feel like I just change the diapers, breast feed him, and wake up at night to take care of him. Sometimes I don't really feel like his mother and I miss many things I used to do before birth or before pregnancy. My boyfriend is attentive with me but often gets angry, and I feel like he thinks I'm a bad mother. I don't feel like a very good mother either. I really don't know how to feel good in my new role and not regret it sometimes:( maybe I'll feel more confident when we move out in couple months, when no one will keep me from really being a mother of my kid and doing it how I think is correct. I hope it makes sense and someone won't find me heartless or something. Maybe someone, especially other young moms, has been in similar situation. I just need some support and encouragement. Cause I don't have much of it here, and my family lives very far away.