im 28 female sedentary lifestyle. had grinding/crunching in both knees since 18. occasional sharp pain in left knee when climbing stairs, putting weight forward when playing tennis etc. used to do tennis and gym light user but would be in a lot of pain afterwards when putting weight on left knee. Couple of months ago was climbing step ladder and felt painful tearing sensation in front inner side of left knee. hot and swollen that evening. now keep getting very sharp pain when climbing up/down stairs then knee is painful ache the whole day regardless of position and swelling comes up on inner front side. im seeing doctor tomorrow but does anyone have advice on pain relief or possible cause? thanks