Go to a physician and have yourself tested for allergies to shellfish and dairy products. It may save your life.
I appreciate what you suggest. I saw references to anaphylaxis about these foods, but neither (by themselves) will evoke a reaction in me, so I do my best to not eat them proximately.
It’s only the combination (or proximity) that will do it, but I can’t find out why.
Maybe it’s just part of being me, but I can’t imagine I’m the only one.