Suffering from knee pain regularly is not normal. If you suffer from knee pain or stiffness frequently, tests should be done to determine the underlying cause(s). Knee pains can be many causes, ranging from Osgood-Schlatter Disease, osteoarthritis, Iliotibial band syndrome, patellofemoral pain syndrome and/or bursitis.
What are the signs and symptoms of knee pain?

Difficulty walking due to instability of the knee
Limping due to discomfort
Locking of the knee (unable to bend the knee)
Redness and swelling
Inability to extend the knee