Any of you have experience of it? I've returned from a long trip, and 24h later I suddenly started developing weird symptoms. I can barely walk, and this morning I noticed the veins up my right calf were all swollen and burst. It's really painful. I am going to the doctors, but my GP is really, well, of limited usefulness sometimes so I wondered if I should be concerned. In total I spent 14 hours in transport on the one day - it's far from the first time I've done it but it's the first time I've had this problem.