HELP!! My 3 year old is acting up!!!!

My daughter is 4 soon and she's not been right for the last two weeks.

She's very aggressive. She keeps saying terrible things to me and her dad!

She's waking up at times in the night screaming shouting horrible stuff like I don't love you, I don't want you, go away, I don't care about you mum.

She's being nasty to her little brother!!! I don't know what has triggered such a dramatic change in her!!!!

All day she's being so fucking hard work I miss my little girl who was kind and lovely. This is almost like my child is possessed!!!!!

What the fuck is going on!!!! She's never been like this!!!!

She's really agressive I don't know why?!!!! I'm not looking for answers just advice !!

Right now it's 11:00pm and she's woke up absolutely screaming like a baby my poor neighbours probably think I'm beating her!!!! She's screaming saying I don't love you, I don't like you, I'm throwing you outside blah blah this is so strange!!!!

I'm calling my health visitor Monday this can't carry on!!!! I don't know how to help her othering then staying calm!!!