Suggest Treatment For Swelling In The Knee

hi my leg has slighlty swollen from the knee down ,its my right knee , it came on about a week ago maybe longer it doent really hurt apart from when i need to bend down its painfull and it constantly achs but when i walk or stand up for even 5 mins its reall hurts all down from the back of my knee right down my calf i have not banged it or anything i cant get my head round it and it is only the one leg please can u help me thanx ...... wendy