Ah, internet hypochondria - it's a beautiful, beautiful thing.
With a little work, you can convince yourself that you have pretty much everything from advanced cholera to a dormant, yet still potentially fatal, form of St. Vitus' Dance to the beginnings of ague - every disease, in fact, known to medical science, bar housemaid's knee.
I offer you the cure devised by Jerome K Jerome's doctor, after a similar bout, prompted by study of the medical journals in the British Museum:
"1 lb. beefsteak, with
1 pt. bitter beer
every 6 hours.
1 ten-mile walk every morning.
1 bed at 11 sharp every night.
And don't stuff up your head with things you don't understand."
Now the best way to make sure it isn't bowel cancer is to take a large knife, the sort you use to hack limbs off of dead animals, and gently and slowly, to avoid damaging the handle, insert it into your rectum.
You many find squatting over a bowl the best way to do this. Now rotate the knife keeping the end of the handle steady and the tip angled to allow a circular slice of your upper colon to be removed intact, withdraw the knife. Now take a long crochet hook and pop it on up your slightly enlarged anus and gently ease the slice out into the bowl.
There you go. You can post the section off to your nearest hospital for histology to have a wee look at and pooh undisturbed without any more thoughts of cancer until the results return.
Want a good laugh? Go to your local cancer clinic and put a partially opened sachet of tomato sauce under a sh1thouse seat. Casually loiter in the waiting room and look at the face of the poor cnut who thinks he's just sh@t his guts out.