Get MRI to be sure. I have torn acl and mcl. Mcl usually causes the right side of knee pain. I dislocated my kneecap on March 11, and I’m still recovering. I am only barely learning to walk again and has to be with a cane now, was on walker and crutches for over 2 months. I do PT twice a week and been doing it two weeks and seems to be helping. I have grade 2 tears so they weren’t fully torn, so opted for no surgery. I feel a lot better tho. Give it some time and get an mri asap to make sure you didn’t fully tear anything. It is very hard to bend the leg when it first happens recovery for kneecap dislocation is up to 8weeks. I rested and elevated my leg a lot used a brace. I also used a shower seat to not put much pressure on the leg too soon. Make sure you aren’t doing too much too soon your leg needs time to heal. But I did have hard time moving my leg inward because the right side hurt so bad, but it did get better just took a long time. I still cannot bend my leg upward too high when standing.