Get your hamstrings checked and also get your knee examined to rule out ligament problems.
I would suggest you to visit an orthopedician to rule out sciatica or any injury to you calf muscles or tend Achilles. You should also rule out conditions like peripheral artery diseases and DVT.
Take NSAIDs and apply ice pack and rest adequately for couple of days.
Thanks. I went to the Dr, and they ruled out DVT. However, they just released me and diagnosed me with Edema. Now my ankle and foot are swelling up too along with my calf. I have been taking NSAIDS but havent really been applying ice that much. It seems really tight and sore especially in the morning but is releaved somewhat during activity such as walking. I am concerned though because the swelling seems to be spreading...any thoughts???