the person called me knew my name and i am affraid of what else he knows

A man called my Unlisted phone number, and asked for my wife by her first name ONLY. I told this man that she wasn't here, and asked Who is calling, and for what Company he works for. All that I got was a First name, and again I asked what the name of the company he is working for. And he repeated what I had just asked of him, and then silence. I hung Up!