I have huge welts on my inner thighs. yesterday it was hot and my legs were rubbing together so i thought it was just chafing but not sure if allergie?

Hives: Hives can be caused by a variety of different things. Certainly pressure on the skin, tight clothing/waistbands, and heat can all cause hives to flare, especially in people who have a tendency to get hives. If no trouble breathing, no wheeze, no cough, no throat swelling, and no other signs of severe allergy, I wouldn't worry. You can try antihistamine for relief.