Itcing is drivin me mad!!!!!?

hi i have itching dwn below on 1 side of my vigina iv bn to the doc n she took a swab which came back clear of any infections doc said its prob jst dry sensetive skin im using e45 by the gallon and no improvment im scratchin at nite in my sleep which makes it really sore, other than feelin itchy the area looks perfectly healthy wat can i do 2 make it go away n wat could it be ? thanks.