since you put down GRAND THEFT AUTO and UNAUTHORISED USE OF A VEHICLE im guessing it was your parents vechicle or some other persons in your household (unless you stole your mothers car one day and the next you stole a strangers). if thats the case then you dont have as much to worry about. you were still stupid though but i dont think you will get much of a sentence as you shouldnt be tried as an adult. Then again it seems you are from the states and they are harsh on this crap so who knows.