You may have had an episode of acid reflux. Stomach is very strong but one of the treatments is to take added hydrocholric acid with meals because even if the stomach acids are not enough to start the digestion of food they are still strong enough to burn in the esophagus and mouth. Also this could have happened if food was not able to pass from the stomach into the small intestine and what was in the stomach backed up instead of going down. If the stomach contents contained something you are alergic to or intoleratant of this would cause more mucus to be produced.
You might stop the Humaworm and go to using Clark's Wormwood and Black-Walnut . The cloves may be causing irritation and that may be true of other spicy spices. Taking B vitamins may help.