Possible Dislocated Knee?

I fell about 5 feet, and when I landed my knee popped and cracked alittle, like three quick pops. I landed with my leg straight and thats why it happened. Maybe I hyper extended the joints or I may have pulled a muscle or I might have a dislocated knee. Im not sure what it is? Should I go to the doctor. It hurts bad and it is difficult to move. It happened today, could it be something I can just walk off and ill be fine in a couple days?