How to leave my child, to return to work?

I just had a baby almost 7 weeks ago. I am starting work back and dreading leaving my little man. He's not going to a daycare he's staying with my mom and my bf dad back and forth when I go back. I work night shift 12hour shifts. I'm just so worried somethings going to happen or he'll cry and just want me (he has done that before cried and just wanted me to hold him close). I'm so sad and so nervous. How did you as moms leave your baby to go back to work again? I 'm going to be an emotional mess my first day. The only good news is I only work 3 days a week. I still need some advice. Thank you all in advance.