I occasionally get the "sunburn pain" on the skin of my right thigh. It is from a pinched nerve in the lumbar region of the spine. My chiropractor does a couple of clicks with his activator on my lumbar and the pain goes away instantly. The numbness comes on when I am standing or walking for a long time but is fairly well relieved when I sit down (shopping with my wife almost always triggers it, as there are few if any places for people to sit down in department stores). The longer I stand, the more intense the pain becomes. The pain is located on the front quarter of my thigh, outside a line drawn down the center front of my thigh. The worst pain is closer to my knee and the pain gradually decreases the higher up my thigh I go, until it disappears about 3/4 of the way up. The pain can become nearly intolerable, so I try very hard to avoid standing for very long.
I understand about the skin pain, i have had the same thing on my upper thigh and lower leg mainly left leg and it is painfull, i have had no redness, no breaking out, i disagree that it could be shingles. I have had them 3 times. they follow a nerve line and you get one chicken pock blister or bite looking thing it is painful and then it spreads. the first time on my left side on my back, 7 years ago, the last 2 times were july 10 and july 11. right arm and right side under right breast. both times on nerver line. What I have on my leg is not no shingles. no coloring, nothing. would love to know what in the heck it is.
This could be the early phase of shingles. If a rash shows up then see a doctor for anti-virals. Or it could be some sort of nerve injury. Rest up for a few days and if no better see a doctor.
Take care.