Every time I take a shower, go swimming in a pool or any type of of water I break out in hives. I also break out in hives when I'm out in the sun and when I sweat. I just get all itchy on my arms, back, stomach and face. It feels like a tingling feeling and they itch; and the hives are usually blotchy. I get stomachaches from drinking water too. What could be causing this? Please help!