Yes!! I'm also having the same moving feelings 15min after eating natto! I know that I have a parasite in the upper stomach/intestine area! For my it is also beneath the rips but on the LEFT side! The Bacteria Subtilis Natto is reacting somehow to the worm. I don't know if it s the rope worm or a Tapeworm -but definitely a freaky huge one! It gets incredibly uncomfortable if the worm starts to move its entire body for a bit of a second. But he only does it when you poke him with the foods he does not like at all! Since yesterday I'm pretty certain that the bacillus from Natto belongs to the food group which provokes this creature! In my case, the reaction often comes with a neurotransmitter release triggered in the stomach area! It can get intense, almost a state of being "high". Natto did have that effect for me this morning and now eating dinner with it again. I'm pretty sure that I have these creatures in the stomach, and by now I know quite a lot about the connection between enteric, autonomic and central nervous system but I would have never dreamed about which strong effects worms and parasites can have on your emotional state. The stomach plays an essential role in all of this! Did you experience other types of foods or herbs etc. which had a similar effect?