I guess it's possible that the large Sugar
intake could have triggered something relating to candida, but I would have expected it to subside after backing off the sweets. You haven't introduced a new food in that time, have you? I recently bought some soy milk which was being liquidated at a discount store. It wasn't until later that I realized it is sweetened with Splenda, an artifical sweetener known for gastro upset. (Most soy milks use modest amounts of basic sweeteners like cane sugar.) Review your foods and drinks for such a hidden problem. Since it happens after eating, this might suggest a food connection, rather than a pathogen. Did anyone else at your celebrations get similarly ill?
As for bugs, my copy of "Prevention Magazine Complete Book of Natural & Medicinal Cures" lists berberine (also found in goldenseal and oregon grape root) as a natural anti-diarrheal in case yours is bacterially caused. It also mentions clove and oregano oil for same. Probiotics, including the better yogurts, are also known anti-diarrheals if bugs are suspected. Astragalus is often taken for viral infections, and possible helpful for viral-caused gut bugs as well. Food poisoning is usually short term and self-limiting, but you might as well read through the symptoms-by-bug outline in the Merck link below, just in case.
Immodium contains a mild narcotic (loperamide). The Prevention book above lists loperamide as likely the best non-prescription anti-diarrheal available, but also suggests using it for only 2-3 days. The books states that absorbent type anti-diarrheals such as kaolin (Parepectolin brand) and attapulgite (Kaopectate brand) are "extremely safe," but take 1-3 days to work. Bismuth subsalicylate (Pepto Bismol) may help as well, and is reasonably safe. Any of the above "cures" should be safe for short term experimentation. If none of this works, your doc, or a gastro specialist, might recommend further treatment and/or clinical diagnosis. Good luck!