Hey buddy,
Sounds like a Meniscal pain - initially not too bad but worsened when you reinjured. When you do your mensicus it's quite hard not to do your MCL as well so I'm gonna say you'v likely done both. Doesn't sound soft tissue - i'd get a second opinion if I were you. We have something we call the terrible triad - where you manage to do MCL ACL and meniscus. Here is hoping you haven't done all 3. But your description of the turn for the ball and your inablity to weight bear following those would indicate you certainly could have. Best to get yourself sorted - go private if need be.
Over the next wee while, locking and giving way are classic signs of meniscus, so pay attention to those symptoms and let the physio/doctor/orthopaedic specialis know that they are happening.
Pudding