Could Lump Behind The Knee Be Due To Posterior Cruciate Ligament Tear?

In 2013 I had a Grade II: PCL tear in my left knee. Never had any issues until last night, was doing running and conditioning drills and have a huge knot feeling on my upper calf behind my knee on my left leg. is this an issue due to the PCL tear and should i be worried of any damage to the ligament or should i be applying pressure and trying to relieve the knot?