Accident and fir

Sir, I am a lady, I am a LLR holder and was driving my car in my street, on a turning a two wheeler came and hit my car when he was trying to over take a van. On humanity basis i called him to hospital in my car. He refused that and came in another two wheeler to near by hospital. In hospital he was discharged immediately after seen by doctor. 3 days after this incident this person started threatening me for money. I told I am going to approach police. before I approach police he went to police station and filed FIR on me. On the same night I went with my petition to police station. They refused to accept my petition and told they put a FIR on my name. Then I asked them what is the procedure?. The police officer informed me that I have to come with two persons to get bail and I have to come and give my signature. The next day I went with 2 persons. They noted down my identification mark , my dress colour and my family details and asked me to put signature in that register. I have put my signature. They did not get signature from the persons accompanied me on that day. They said they want to enter all the things in online and the computer operator did not come on that day. Now they are refusing to give FIR copy and asking me the orginal documents of car. what should I do now?