Severe crippling mom guilt

I lost my mind on my 5 year old tonight. I yelled like i have never ever yelled before. I am 35 weeks pregnant scheduled for csection may 6th. High blood pressure, anemia, gestationaldiabetes. It wa time for bed and she constantly trys to push my boundaries. Well, she started screaming her lungs out and threatening to smash the thermometer on tje floor. I tried being calm. I said no several times sternly and she kept going. And i lost it. I screamed for her to go to room and she sobbed the whole way up. I apologized to her and told her I should not have yelled like that. My blood pressure 179/99 the highest its been. I was.literally seeing stars. How could I do this to her? Ive never been so stressed in my whole life. I work full time. Im in RN school full time. I cant.afford groceries. I feel like the whole world is literally crumbling down.