Every time I bend my knees, they pop and it hurts a little bit.. then when im crouching, like when I m catching in baseball, when I stand up, as I m standing I feel a sharp pain in both knees.. Also, when I m doing leg workouts at the gym, sometimes my knees start to cause me trouble when bent. I m wondering if I have any sort of knee problem that I should have, or should be taking care of.