i fell off of my bike and i bumped my right knee hard on the upper left level of my knee-cap. It is a little bit swollen and bruised but i can walk fine and perfect but when i place my finger on the part that swells, and move my knee at the same time, it clicks and it feels like a small string is moving by an inch. It doesnt seem serious but im scared that it is bad. Can you tell me what is happening? thanks.

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Male, Age: 18, Vietnam

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