Vilkas is acting like a guard and i cant stop him

I had a fight in White Run and Vilkas was attacking me. When I came back from jail he started acting like a guard- chasing me with weapon and starting a dialogue. I tried injuring him and it didnt work. Please help.

This is normal

As a follower, Vilkas has no tolerance for crime. If the Dragonborn has a bounty in any hold, Vilkas will draw his sword and advance on the Dragonborn, but will not attack unless provoked

To fix this you need to go to the White Run and pay for your crimes! As well as all the other holds you have bounties in

Source: http://elderscrolls.wikia.com/wiki/Vilkas