How To Get Rid Of Sunburn From Armpit To Back Of Hip?

My skin feels like it is sunburned. Very sensitive to the touch. In 2 places: on the left side of my body just down from my armpit and on the back of my left hip. I have had this feeling for several days. There is no rash or anything on my skin in these places. I already had the chicken pox when I was an infant.