I keep getting chills down my left leg--not an unpleasant sensation, but rather the feeling that someone is lightly tracing their finger down your leg, and leaving an almost pleasant chilly-goosebump sensation behind. Except no one's touching me. And it won't stop. It was coming and going but has been fairly steady all day today. I don't know if I'm just noticing it more, or what. I am a workout fiend but haven't done anything new or different lately to cause an injury or pinched nerve (that I know of.) What could be causing this? Every time I go to the doctor with a vague symptom (which I rarely do, maybe 5 visits in 10 years) they don't do anything but tell me I'm probably anxious (I'm not)! I'm terrified it's something crazy like MS but I don't have any other symptoms. Please help!