Hi Sheel,

I saw your post when I was on another forum and I felt I should reply. My husband had a colonoscopy last Tuesday and we were beside ourselves as my husband had an Oesophagectomy in May 21 for Oesophageal cancer. Fortunately his colonoscopy didn't show any cancer but 3 polyps were removed. We weren't told the amount of blood but like you he couldn't see any blood himself. No one can say 'don't worry' as anyone would and more so because of your family history but what I would say is try not to panic. As I'm sure you are aware 9 out of 10 colonoscopy's do not result in a diagnosis of cancer. My husband thought long and hard about having sedation as he has been through a lot but in the end opted not to and although it was a little uncomfortable he was as absolutely fine and no after effects of the anestetic.
Regarding going private obviously it's your decision but we found the NHS brilliant and you shouldn't have to wait too long at all for the colonoscopy. My husband had an appointment a couple of weeks before the procedure which can be done by phone but we asked to go in as his surgery was massive. On a final note please remember that the colonoscopy aims to prevent cancer from starting or to find it early so it's treatable but is also used to check for diviculitus, polyps, haemoroids amongst other things. 

I hope this helps.

Keeping the faith (sorry I always write this)

Milly