Ok, so for the past 1.5 years I've been practicing brazilian jiu jitsu pretty intensely, 4 times a week and for maybe 2-3 hours each time. Bjj = submission wrestling. So as of late, I've noticed more and more pain coming to my left knee and shin until now its just unbearable to even touch the skin. When i am actually grappling, I hardly feel the pain, but before and after the practice it kills. Any advice as to what I should do?