Will these painful sun rashes scar my skin?

Depends on how bad. A sunburn is just that, a burn. Burns can be classified as 1st, 2nd, or 3rd degree. A mild sunburn, 1st degree, will get red and sore but will probably heal without scarring. A severe sunburn is like a 2nd degree burn with blistering of the skin. This more often can lead to freckling or scarring. Overexposure to the sun, regardless of burning, increases your risk of skin cancer later in life.