How long do you have to file an assault and battery in NC?

i live with my mother in law who works at the tax office in NC and we got into an argument and she jumped up in my face so my husband got in between us and pushed her back and she started swinging around him about three or four times til he got her into the corner then she twirled around him and hit me in my face knocking my glasses into my eye socket in front of my husband and my two year old son. I called the police but when they showed up all they said was to go to the magistrates office and file charges. So what I need to know is how long do I have to file charges and since we live in the same house, us upstairs, is it possible to get a restraining order against her? Oh and we can't move out just yet, we were in the process of saving to get out but now pressed for time and have no where to go. Please Help. Thanks.