Skin burns/itches if I get in the sun (spf45 & umbrella) also fatigue/nausea after exposure. syndromes?

My skin burns bright red even after 2 hrs in sun with spf 45, others around me aren't evening wearing sunscreen, and they are not burning, my skin is also very itchy after being in the sun, to the point that it is painful when I keep scratching on the freshly burned skin, but I can't stop--it just itches too much. I come inside after being out, my skin feels on fire, I have a headache, nausea, and I am extremely tired, so much that I have to take a nap. When these episodes have occurred (3 times in the last month), I have not been working or exercising, I have kept hydrated while I was outside. I am not taking any medication. My heritage is: Part italian, american indian, & german, I have dark hair and eyes, fair skin, I used to burn in the sun the first time, then tan through the summer (when i was out, on saturdays only--I have an inside job for the majority of the strong sun hours). I am wondering if this is some sort of disorder, syndrome, disease. I know I feel very ill.

There are several conditions that involve symptoms of sun sensitivity, including Lupus and Sjogrens Syndrome.

See a doctor and tell them the problems you have experienced.

Keep a diary of your symptoms, if you were in direct or indirect sunlight, indoors (i.e. via sun windows), the exact symptoms and in what order they occurred, how long the sun exposure was, and anything else you feel relevant. Include symptoms that you have that you may not have attributed to the sun exposure (headache, dhiarhhea, anything else). Share this with the doctor. Get more than one opinion if needed.

sounds like heat exaustion