Some children get in the screaming mode and have a hard time stopping. My child gets in the crying mode and then can't stop crying. Do not give her attention when she is screaming. Give her lots of attention when she is calm and behaving nicely. If she whines, I would say firmly "I do not like it when you whine". If she screams at home, I would just ignore it or do something like vacuum so she can't heard herself screaming. She will get tired of it, if she's not getting any attention. She is trying to figure out a way to get control. She may be frustrated. Make sure she has lots of choices and feels like she has some control like what she wants to wear that day. Children yearn for control and everyone wants to feel like they have some control. However, do not give her any form of attention for screaming or whining and let her know that she is not going to get any attention from you until she stops.
Who is it she is bossing and bullying has she a sibling?What has happened prior to the screaming to upset her, does she go to day care or pre school if she does what is her behavior like there. Focus on her positive side ,and give her plenty of attention. choildren of this age dont want to sit around a lot they are always on the go and , check whether she is sleeping during the day as maybe she finds she has energy at night.,