Got a controlling boyfreind and a sis in law who is threatning to beat my *** iff..?

i got a 2 wk old baby yes hes the daddy but i know that im not happy here and im wanting to take my daughter with me. i got a place to go. i wanna leave today. shld i call the cops so nothing happns to me n the baby are leaving? what will they do? and i just found out today my soon to be exes sis in law n her husband is gettn a divorce so he can go his own way and me n the baby go ours. cuz since theyre brok up they will lose where we stay so i should go right? just for the safety of my daughter . and im not happy with him anyways. plus i need the cops to protect me and my daughter from his sis and law and him. cuz he will put his hands on me and try to hold me down. he is very controlling and i cant take it anymore.