My head is always hot, achy and heavy, like I have a fever. But the rest of my body is normal. Sometimes my hands and feet are cold while my head is hot. I also have become more heat intolerant. When I'm exposed to heat my arms & legs become very weak, i'm underweight to my age and I'm generally weak all the time. I also get mild eye pain. However, I never seem to sweat from my forehead, only under arms. But when I get really cold it's really hard for me to warm up (my toes go numb). Does anyone know whats wrong with me?