Is this a normal feeling to have?

I failed my driving test two times. I have yet to take it again. If I fail again I envision taking a gun, shooting my ***** test instructor and then shooting myself. I know I will not ever act on that feeling. I'm to much of a and I don't own a gun. Is it so wrong for me to think that way? I'm a 16 year old girl and I'm fed up with authority. I've had the same instructor both times and shes much too harsh and unfair. I've had it. The only consolation I have is envisioning how I would hurt her, although I will never act it out. Is that bad?