What are my rights concerning domestic assault?

After a traffic altercation, a man followed me to my garage, parked behind my car and started yelling obscenities. I went to his passenger window to engage in some return yelling. I leaned into the car. He and I were flailing hands with gestures while screaming at one another. I grabbed his wrist momentarily, let go within a split second of realizing I was touching him. He filed domestic assault charges. I was contacted by a police officer today over the phone to take my side of the story. The officer states that the party had "red marks on his wrist when he reported the assault." The police will send the case to the county attorney for a decision whether to prosecute. What do I need to do? This crackpot started the traffic altercation, I tried to speed away. He ends up following me right to my garage, actually blocking me from exiting. I know I should have just closed the garage door and walked away, but that was not my response. If anyone had fear of bodily harm, it was me. I didn't know what the lunatic was going to do. What can I do?