Hey

I've been through and am still going through a very similar situation that's been going on for about 9 months regarding seeing random areas of blood on my stool and once on the paper. I saw a specialist last week and he checked my rectum and lower end of my sigmoid colon and found nothing but said one of my hemorrhoid veins (we all have 3 anyway but it's when they swell that it causes a problem) looks swollen so that could be what's bleeding

I'm not a doctor but my understanding is that bowel cancer usually bleeds A LOT and is very consistent in its bleeding patterns. Blood tends to sort of "explode" in the toilet bowl along with diarrhoea, but even that could be a simple burst hemorrhoid

The fact that you haven't seen blood since improving your diet is very reassuring because it shows that a low fiber diet, in your case = blood.

That would make the cause a low fiber diet, so you could be irritating hemorrhoids or you could have a fissure.

Also you're from the USA? Over a four year period of time within the last 10 years I think, only 0.1% of new cases of bowel cancer were diagnosed in under 20 year olds in the USA. That's a very small number