If it was just your knee cap, no. If you actually have a dislocated knee, yes.

Hi,

I would definitely go to the hospital, an urgent care center or an orthopedic doctor as soon as possible if you have a dislocated knee. Do you want to make sure this gets put back in place so the tissues around can heal?
I hope you’re feeling better.

I am assuming you mean a dislocated knee cap (patella--the bone in the front of your knee that is part of your quadriceps tendon [the quadriceps is the big muscle in the front of your thigh]). Were you able to put it back in place? Is you knee very swollen with a lot of 'fluid in the joint'? Is it still very painful? Can you walk on the affected leg without too much pain? Have you had problems/injuries with that knee before? If there is any question in your mind whether or not you have a fracture (broken bone) or if you are unable to bear ANY weight on your leg, then go the Emergency Department immediately and get an X-ray and definitive treatment. If you have persistent pain or swelling, see an orthopedic surgeon as soon as you can so he can evaluate it.

yes

Yes, there could be other damage to bone and soft tissue in the area.

You should call 911. A dislocated knee is an emergency because of the risk of damage to the popliteal artery that runs the back of the knee, possible fracture, and pain control.

YES!

You should go to a Sports medicine facility.