I have been going going to the ER the past 4 days with the same problem and they keep telling me that nothing is wrong I have had a CT Scan and an Ultra Sound both coming back negative for blood clots. I am having alot of pain from my buttocks and groin area going straight down to my calf of my left leg. I have enlarged veins on this leg and they are so swollen. I am starting to have difficulty being on my feet too long. When my legs had been measured my left calf area was 2 inches larger than my right calf and it has not gone down at all. I really thought i had a blood clot in the vein and the ultra sound came back negative. A day later I was still having alot of pain and discomfort and the swelling still didn't go down so I returned to the ER and the physician thought that maybe the clot was in my artery so I was given a CT Scan and low and behold that came back negative. I just don't know what it can be I am not sleeping very well because of the pain has anyone any idea of what you think could be wrong. I am a 52 year old male, very good physical condition, usually exercise regularly however I have been unable to work out lately. Any help would be greatly appreciated.