I pumped leaded gas into my 06 Infiniti G35 which takes unleaded only, what to do?

I just pumped 112 Octane LEADED gas into my car by mistake, (idiot i know), I was at the race track and instead of unleaded i pumped the other one by mistake. ANYWAY i had about half a tank of 92octane in the tank already, and I added 5 gallons of 112octane LEADED, noticed it was leaded after I put the 5 gallons so I then finished it off with 5 more gallons of 100octane UNLEADED. As I drove my car through the night I heard a mild knocking, crackling coming from the engine, what damage can be done to my car because of this mistake? How can I fix it? What can I do??