Taking care of a 3 year old and a new born as a working mom

I’m 12w5d pregnant with my second one. Every time i think about taking care of both of them while working full time in a very stressful environment, I freak out. My husband help a lot but his job is just as stressful as mine. We decided not asking his or my parents for help after I deliver since we are living in a small apartment very far away from them. My 3 yr old is at day care full time 5 days a week. I will have max 6 weeks for maternity leave if i want to keep my job. Please give me any tips and advice about how to organize time and work to take good care of my two LOs