I get the same thing. Not always but frequently.I would have rise of fight and flight, via my "belly" and the vagus nerve system. It is worse in the morning and better in the evening. It is definitely after eating, and I would give much to know what it is related to.
One weird thing started happening though. I found I'd burst in to tears after eating. Not from any sad thoughts or depression, but like a reflex that I had no control over. When the tears finished (not long -maybe 3 minutes) the other feeling passed, and I could sense my belly accept the food and start the rest-and -digest stuff. (parasympathetic nervous system)
So for some reason, crying must have flipped a switch from Sympathetic to parasympathetic.
My theory is it has something to do with acetylcholine and acetylcholinesterase. I am still working on the analysis of that.