Allergy test I took to nuts, fish, milk, soy, was negative. This means, there is no reason for the tongue to swell, and kill me? I have health anxiety

Allergy tests. The tests you had done were food allergens. Although it is encouraging that they are negative, there are other things you could be allergic to, such as aeroallergens: pollens, grasses, trees, weeds and even animals. Any kind of a reaction to allergen could cause tongue swelling. There are other causes of tongue swelling, but allergies & trauma are most common. Not common to kill, though.