Pregnant with toddler

OMG guys, how do you handle being pregnant with little ones running around. After a 9 hour stressful day at work, I come home to a very active 3 year old. Make dinner, play with her and get her off to bed. Tonight she refused to go to bed at her normal bed time (7:30/8PM)... As it was approaching 9PM I couldn't handle her antics any longer, I lost it and screamed at her. I could feel my blood pressure sky rocket and upon screaming I felt something tearing in my belly. I feel nauseous and exhausted, I have no energy. I'm so drained. How can I keep up with my full time job and family, on top of being pregnant. Can't imagine what it'll be like adding a newborn to the mix..