I break out with a blotchy rash that spreads when im in the sun, hot shower, eat hot food or when i get upset what could it be?

Urticaria: You may have cholenergic urticaria which cause you to break out from heat sources.

Hives: It sounds as if you are having a dermatologic condition called urticaria. Urticaria is the medical terminology for hives. It is the bodies response to a certain stimulus, such as an allergy. The body will release histamine in response to a stimulus and histamine causes redness, swelling and itching. Other triggers of urticaria can be cold/heat, stress, medicines, or foods to name a few.