I was on my phone last night, so linking is very difficult for me.

If this is a "new" event, then you need to be a detective to see what is new for you.

Things like mastocytosis would be present since childhood, so this extreme form of histamine release would not be new to you.

But carcinoid and tumors would come on slowly. Carcinoid tumors in the GI tract would dump the serotonin in the liver for a long time until they metastasize outside the liver, and then the symptoms of flushing, wheezing, etc begin. Hidden lung tumors typically show up with flushing and sometimes behavior changes as the serotonin builds up in the body.

The major cause, would be the various drugs. Next comes foods.
In children often the first sign of food intolerance is bright red ears and/or face.

In adults the single most common flushing cause is alcohol use.
This can change with time and severity to become a purplish hue of the head neck and face which some advanced alcoholics display.