I Fucked Up Big Time

My sister and partner were staying at house. he does not legally live here, she does. He is a known verbal and emotional abuser and my whole family has beared witness to this. He has stalked and shes had several police involvements with him before. The other night i heard him and her arguing to which she told him to leave and not come back, he got verbally agrresive and i heard a scream of pain which I assumed to be him placing his hands on her. I didnt think (this was the big mistake) and brought in my knife to scare him away and to leave. He was not intimated at all, and got verbally agreesive with me. At this point i knew the best course of action was to out the knife away on a table away from us and create distance between us. He was trynna physcially fight me afterwards and made threats to show up to my work. He then ounched a hole in our wall. Yes, i know i made the dumbest stupidest decision ever. I thought my sister was in danger and i didnt think. We were both booked and now i have several charges, him as well. Misdemeanors. menacing, possesion of weapon in 4th degree. Ny law. in his report he was, very breif he just mentioned that i pulled a knife on him to scare him. Which yes true, but he never provided the full story. He said hes willing to drop the charges. I just want to know what the best course of action is after getting a lawyer. and if ill have a defense because of all the verbal abuse and other incidents reported. I am still shaken and idk what if he decides to backtrack on dropping the charges. Basically, am I fucked. i am freaking out, we were both released, and have our court dates set.