Behind Knee Injury

tempo4100

 I stopped running for about two weeks and now two days ago I ran a 10k in average time, after the run I done some skipping, sprints etc. Behind my left knee is sore and I don’t think it’s muscle that is hurt. Walking fast and stretching my leg hurts. 

<div>Does anyone know the name for the area that’s hurt and how to help heal it?
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</span></div><div><span>Thank you so much </span>
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