this is better in the injury forum. But...
it could be a problem. you may have actually destroyed your acl/pcl actually. or any other knee structure. If you went to a doc, they'd probably recommend a MRI, or just therapy for conservative measures. regardless I would recommend the following:
See a chiro--comply with any imaging he/she requests (likely)
Work with a PT to stabilize and train the joint for stability and recovery.
Knees are one of the most frequently injured joints... you gotta take care of it, or basically lose your mobility toward the later parts of life--you don't want that.
Good luck.