Oh I hear ya!!

I am very pale and I was in the sun for 10 minutes on Saturday and my chest is red and blistering! I avoid sunbeds like the plague as my only experience is the same as yours - burnt bum cheeks and boobies!!!

I would get some aloe vera sun spray from the supermarket and put it in the fridge to cool. Once it's cold, spray it on the burn and it should sooth it.

I wouldn't use moisturiser as it tends to heat up on the burn and can make it worse. It won't sooth it. You need aloe vera!!!