Can I fight this? I don't think I should've failed for this.?

I failed my driving test yesterday because the lady marked a Critical Driving Error. It was marked as a "Dangerous Manuever" and in the comments it said that this was for not looking over my shoulder while going into the left turn lane at the stoplight (twice). I know that looking over your shoulder is a must when changing lanes, but while going into a turn lane where no one should be driving over there until the dividing line curves out, I do not see the reason for me to fail because of that. The Critical Driving Error section is an automatic fail if one I marked, I do not think I should've failed for that. I understand points docked, but automatic fail? I would've passed because I only had 5 other things marked. Can they really fail me for this?