Every now and again I will randomly get a biting/stabbing pain in my knee. It used to happen during the night and I would wake up with pain and couldn't sleep until I took pain relief. But now It happens during the day. I dislocated my left knee a few years ago and it used to happen in that knee only so we thought it had to do with that, we also thought it could be because I keep it in a twisted position while I sleep (no evidence) It has no pattern and I don't usually remember how it starts.