Last November, I was experiencing pain in my left calf. It felt like a charlie horse except it wouldn't go away. I had a doctor's appointment coming up soon so I waited until I went in. The doctor said it was nothing and sent me home. One week to the day, I collasped at home and rushed to the hospital. I had four clots in the left calf, three in the right calf and clots in both lungs. I was flat on my back for seven days while they put me on coumidin, a blood thinner. If you continue to have pain in your calf, I would run not walk to the doctors and tell him or her your concerns. I will be on the blood thinner for the rest of my life. I am 60 and was scared outof my wits. They told me at the hospital that I must have been sitting alot and that is how the clots are helped along. We had taken several extended bus tour trips in 2002 and they feel that allowed the clots to form. I still am a little nervous about them but, I am assured that clots rarely return while on the blood thinner. I hope I have been of some help.