Make sure your hip is moving correctly. Lay down and do a few clam shells, make sure you glute is abducting your leg, and that your hip flexor isn't acting up and doing the work.
I'm not super experienced in BJJ but I imagine that it would be easy to develop weird movement patterns after getting into those crazy positions. Especially in the hips, when in your guard position, with your legs and feet going all over the place.
Be sure to roll those IT bands and stretch your quads as well.