How do I reduce swelling in my feet, hands and calves in the heat and why do my calf muscels keep twitching?

Hi all. Arrived 3 weeks ago on a lengthy contract - been visiting since 2006. This time however, my hands, feet, calves ....basically whole body is constantly swollen and my calf muscules are jumping and twitching at rest. Can anyone suggest why this may be and how to combat it. Normally when I work here, I am healthy than anywhere else in the world!
Advice please!!