My 3 year old is bad a** hell! I need help

First off excuse the language in the title. It’s how I feel in the moment, I absolutely adore my child but man some days are tough. I came here to vent and to possibly find another mom with a similar situation.

My daughter is 3 and I just can’t get her to listen. I know she’s only 3 I don’t expect her to listen like a 20 year old but I wonder if her behavior needs to be seen by a behavioral therapist.

She was potty trained at 2 1/2 years old and about 3 months ago she regressed and is back to using pull ups. She won’t go to the restroom anymore. That could have something to do with me giving birth to my 3rd baby on her birthday month when she was turning 3.

She’ll empty snack containers on the floor , spill drinks on purpose, she recently cut her hair off she’ll cry if she doesn’t get her way and won’t stop until she does, and many more things I can’t think of right now, I know these are all very common 3 year old behavior I guess I want to know when this stage is over.

My oldest wasn’t like this so this is all new to me. And now with my 3rd baby I’m like god help me because I cannot with my 2nd child