Think My Ex Is Trying To Kill Me...Please Help?

I left my physically and mentally ex two months ago. He gave me two black eyes, stole from me, lied, cheated, etc. Two weeks ago, I posted a question on yahoo answers about abusive relationships. Thereafter, a person with a screen name that matches my ex's nickname responded. The person placed a dot in the answer box and did not provide an actuall answer. Also, the person became a member on the same day I left my ex. Later, I changed all my pcodes and blocked him from facebook. Then I found out someone installed a keylogger on my computer. Subsequently, my facebook pcode was changed again without my permission and now I cannot access my account. Today, I was driving him and my car suddenly started to lock. The dealer said someone cut my accessory belt. I am afraid. Do you think I am over reacting?