| Welcome to the forum but you didn't have to wait until you destroyed you car to chime in. E85 is 85% alcohol and you car is not mean to run on it, so it will run poorly, probably misfire codes. I doubt one tankful makes a huge difference in the life of your engine and if you car runs OK just burn it through, otherwise empty as much as possible and fill it up again with premium. Most gasolines now have 10-15% alcohol anyway.
Resetting the light is easy, just get a OBD2 scanner, plug it in (connector is near the parking brake release handle) and reset it. These days it's crucial to have a scanner to do any work on the car yourself. | 
