I am no expert but will say that 13 is very much on the lower end when it comes to positive tests. As you likely know, the cutoff for a positive is 10 and some people get results way into the 100s. Especially after a negative test so recently, I would say there is a good chance your positve result is just caused by something like piles or a little cut. 

I don't think the older pre-FIT test would even have registered that as being positive, though I could be wrong on that one.

I also just read that 10-15% of those who do a FIT test will get a positive result so it doesn't mean cancer is at all likely. Just that they have to rule it out.

I know that is limited consolation as there is no way of being 100% sure you don't have cancer until you've had the colonoscopy, but the odds are against it and one good thing is that you will know soon. 

Hi

Im 58 and had a positive FIT test earlier this year.  i was referred under the 2 week rule for a colonoscopy and was pretty scared.  The bowel cleanser wasnt too great but totally doable.  Thankfully nothing found other than internal heamorroids (sorry not sure how to spell that)  I hope all goes well.

I am worried atm too as I had 3 uterine polyps removed a couple of weeks ag.  The gyne said they looked benign and he wasnt worried and that my womb looked normal and he'd write with the results.  Then I got a call saying he wants to see me urgently - I cant think of anything else - appointment is tomorrow xx