I got a serious sunburn in Florida a few months ago. This is what I recommend; go to your health food store and buy some pure aloe vera gel. Make sure it's the kind that has to be refrigerated, this way it contains no synthetic additives of preservatives that can hinder the effectiveness of the aloe. It will also feel nice and icy against your sunburn. You can sleep with cold damp towels on the area. Keep it clean, apply the aloe, and maybe try lavender oil or colloidal silver. Feel better!
aloe vera is great if your going to use Gold Bond, don't use the powder. there is a Gold Bond cream that will help with the pain.
white vinegar works great on sunburn!!! take and saturate a wash cloth in it( i know its not so great smelling) and lay the cloth on your skin til it gets warm...once you can't stand it, pour more on the cloth...i once was so burnt i couldn't even move, i had to lay down, and have this applied to my back...it does stink, but it takes out the burn and pain very well...after the burn is gone and you can handle it being touched, apply pure aloe(from the plant is best) to all area's of burn...reapply every 2 hours or as needed
i second the vinegar suggestion, my grandma swears by it. it stops it from peeling and takes some of the sting away.