Hi about 8 months ago I knelt down and my knee popped and lots of pain, few hours later I got huge bruise over knee cap. Same thing happen on same knee 5 months ago! Today Ive knelt down and again pop and knee hurts so much but no bruise! Its aching and feels sore and when I extend my leg it hurts so much! Feels like my knee dosages he's from lower part on leg! Been to doctors last two times and no explaintion! Please help!