I am 27 years old and live a mostly healthy lifestyle. I am at a healthy weight, exercise 2-3 days a week, but travel very often, which can inhibit my goals of eating healthy and working out more. I am also sitting often as I travel by car or plane multiple times per week. For months I have had dull pain localized to the lateral side of my left calf and my legs fall asleep or become numb often. This was nothing more than a nuisance until I work up yesterday with considerable pain in my left leg. At first I thought I had shin splints from my running regimen, but as the pain worsened as I sat through a seminar. By the end of the day, after driving 4 hours home, my leg had run the gam met... The pain had generalized, running clear up my thigh and to my toes, it had become cold to the touch, prickly, and my toes were visibly purple in comparison to the right leg/foot. My doctor advised me to go to the ER immediately where they did an ultrasound and found nothing! What could it be and what should I do next??!