Parenting: How to stop yelling in anger?

My 4 year old has tantrums at times. When I am PMSing, I am quick to snap and yell and scream. How do I slow down in those moments so that I can decide to not yell? Today she was crying on the floor when I went upstairs to the bathroom (in a rush), then led to her crying and me screaming at lunch because we had to leave to go to a doctor’s appointment (in a rush). How do I stop in the moment when everything is rushed? Honestly, feeling the vibration of anger seems so much harder than screaming. I dont know if I can stop myself.