AAbout 6 weeks ago i knelt down sitting so my feet were under my butt and as i did so my left knee popped and right about my knee cap something pulled. It sounded like when you pull a chicken leg off a cooked chicken. Immediately it hurt but i thought maybe i just pulled It a little too far. I stood up and felt weakness and pain throughout the day i had pain while i was putting pressure thru my heel. So like doing stairs. .especially going down. Now i can t bend my leg back and forth at the knee without it getting locked at 90 degrees with excruciating pain. It has been like this for 5 days. I have been icing, ibuprofin, elevating trying to keep the range of motion even though it is killing me to do it. About 7 days ago it felt full or pressure on the inside of my knee. I can t sleep because it burns all night. Help.