"Painful colonoscopy"

I had a colonoscopy yesterday which had to be abandoned because I was in so much pain.Other people who have had this done have said they didn't remember anything about it afterwards whereas I remember every minute.The anaesthetic didn't seem to have much effect and even though the staff could see how much pain I was in I wasn't offered pain relief.Now I have to go through all the prep again to have a ct scan-what a waste of nhs resources as well as leaving me feeling upset by the whole experience.I will tell anyone who is going for this procedure to refuse to have it unless they are offered adequate anaesthetic and pain relief.