Thanks for writing to the forum!
Urticaria is usually triggered by allergens, such as drugs, foods, insect bites, inhaled substances, in response to sunlight, cold, heat, stress, exercise, or a viral infection. Other common allergens are pollen, mold, dust, pet dander, or cosmetics.
In your case since this was associated with vomiting it could be a food item you ate or a drug you took for something.
It is difficult to comment beyond this at this stage .