Unless you have had huge issues with moving of/clutch control/observations etc, then yes, you are being seriously ripped off. Everyone is different but I was on mainish roads on my first lesson and starting to drive between towns and properly getting into the maneuvers by my 3rd-4th, and that was my first exp driving.
Like if most all you do is drive up and down this one single road, then pull over and he tells you what you're doing wrong, what IS he saying you're doing wrong? and what is he then forgetting about since you've barely done anything?
Is this person actually a professional Approved Driving Instructor? because they kind of sound like an amateur, no structure, no feedback, no progression, almost like they're hoping you'll tell them what they're job is supposed to be.