Thank you for your query at DoctorSpring.com
It looks from your details that you had suffered from a twisting injury of knee.There are chances that there may be some internal derangement of internal structures.This should be put in differential diagnosis in cases where there is history of giving away at knee,history of locking or difficulty in folding at knee. It looks that you are not having any one of them.In that case please do not strain your knee for at least 3 weeks.
Hope this will helps,
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