Muscle Pain Behind The Knee Can You Have Sprained Knee, But The Pain Comes From Behind?

Can you have sprained knee, but the pain comes from behind? - muscle pain behind the knee

I've had more exercise lately, and last week I tried to run / walk, instead of walking. I felt good during and after, but the next day and all last week, I still feel a slight pain in his knee, and seems to be worse behind the knee and below the calf area. Well, a week after Mars, the injured muscles behind my knee and the calf in the vicinity of each movement. The pain is not unbearable, but was getting worse. What should I do? I am very concerned because I am not going to the doctor.