It was die-off. If it had been a direct reaction to the HUMAWORM - you would have had the bleeding and explosive gas from day 1. Toxins and parasite removal can cause very very foul gas and stools.
Diarrhea (and vomiting) is how the body gets rid of harmful things quickly - and I think this is how your body is getting rid of the parasites and toxins that HUMAWORM has pulled out. Your colitis may be caused from a microscopic parasite.
2 1/2 weeks are better than none and if you decide to try to parasite cleanse again - do wait 90 days.