shocking jolted knee pain please help

I am a professional dancer one night after practicing several hours... i started to get a jolting sharp pain on my left knee i think coming from the knee cap or around the sides of the knee cap. it went away the next day but came back again few days later...... it seems to come when i just walk on the knee not every step but a certain pressure of my steps. Someone please help dancing is my Job and before i dish out money to a doctor i would like to try to understand what im dealing with. PLEASE HELP!

[VirginiaW]

I was 15 days without an attack. I had one jolt in a swimming pool this morning.
My MRI had showed nothing but common age-related ailments around my knee . . . nothing that would cause electric-shock like pain. I do have a small Baker's cyst but was told that they are no longer removed because they come back.
Yesterday all day I had lower back (below the waist) pain and feeling of swelling around my knee. I'm realizing that the lower back pain is often a precursor to knee attacks.