This is a bit of an odd one but I'm not sure if its worth a trip to the gp.
When I'm in the shower and I stand with my face under the hot water to wash my face I get a pain in my forehead kind of behind my eyes. It also happened when I opened the oven and the hot steam went in my face.
No other headaches at all, the pain is momentary and stops as soon as the heat goes away. No problems with eyesight. Any ideas gratefully received.