Thanks for your reply DesertSphinx.
I think you are dead right about my sub-concious probably not being happy with my job. My last job involved a lot of studying initially and despite having passed plenty of exams before, I hit a brick wall after a few months and left that job. To study well I have always needed an inspiring goal, I obviously didn't have it in that job. I shall try and ponder which of either Natural Brilliance or Tony Robbins will help me get over missed opportunities and mistakes in the past, help pick me up and enable me to move on and find a job I enjoy.
Best wishes
Glenn M