"They forgot what I was supposed to be having done"

I was booked in for an endometrial ablation at Lewisham hospital and was talked through the procedure before being taken down to theatre. When I woke up the Dr who had explained the procedure came to me and said that they had performed a biopsy but would have me back in 6 weeks for the ablation. When I queried that this was what I had come in for the doctor said that they did not have the correct equipment in theatre. I asked to see the consultant so they went and got him and when they came back the doctor said, I need to apologise I actually forgot what you were supposed to be having done. I had to go again a week later to have the correct procedure. When I put in a complaint the doctor denied lying and I was basically told that mistakes happen. I think the doctors consultant was the head of complaints for the hospital so I found I was unable to progress the complaint any further.