Ouch! I'm sorry. Ice for sure, and keep off your feet. That sounds painful.
Oh my oh my oh my. Ouch is right. I agree that ice would be best and a nonsteroidal like ibuprofen. What did your doctor say? How did that visit go and how are you now??? Tell us what happened!
Dislocation of the patella (kneecap) is usually an isolated traumatic event (often seen with basketball, football, and soccer players), but can be recurrent in patients anatomically predisposed (shallow trochlear groove, patellar morphology). Although you have put the kneecap back in place, there may be residual damage, such as edema or disruption of medial patellofemoral ligament, subchondral marrow contusions in medial patella and lateral femoral condyle, and/or chondral injury to the patella. If your symptoms, consider MRI knee without contrast.