For the past 4 years I have suffered back pain only when I rest or lie on my back on my right side just above my bum. I struggle to stand up the pain is severe but when I do get up and walk the pain eases and goes. I don't know why it just does. I've had excessive sweating as well where I sweat at the slightest thing. My body overheats as well just by minor exertion. Just walking round my house cleaning brings on excessive sweating and I have to sit and cool down. I've been to the docs who say they can't find anything wrong because my blood tests are normal. What could it be?