I'm so happy that my SO starts his new job tomorrow morning, but that being said I'm slightly…

I'm so happy that my SO starts his new job tomorrow morning, but that being said I'm slightly panicking cause of the transition. He will go to work at 8am not knowing what time he gets off till he knows what job he will be doing. He has been doing night shifts with our 2 week old, waking up every 3-4 hours to feed and change diapers. When we first brought her home everything was basically put all on me. I was doing everything while he helped out here and there. It got to the point I wasn't eating, I was so drained & stressed it was making me sick. Where I felt like walking death. We had a long talk and the past 2 nights he has been such a big help and letting me sleep at night. I'm so worried things are going to go back to how they were. Any tips?