Sports Injury

Knee sprain

About over a month ago I had an accident and I don't remember how I fell, but I sprained my knee. Now it doesn't hurt anymore but I can't straighten it properly. It's almost straight but just won't go the last 2 inches. It feels uncomfortable to try..

it needs cracking a lot too and constantly feels... 'odd'

Any idea what this is and if it's fixable??