Whats wrong with my knee, feels like i extended it too far, sore and pops every time i crouch?

its not intense pain but my knee feels sort of hollow. seems like the kind of injury if you jumped too hard oof 1 leg in basketball and it stretched too far...cant pinpoint the paint but i think its popping at the top front of my knee. had this problem last year for about a year and it got better and i was able to play basketball again. but it just kinda happened out of the blue this time.