This can be due to vulvodynia which can be due to many causes
like persistent vaginal yeast infection
, irritation to antifungal treatment , sensitivity or allergy to something touching the vulva, such as soap or bubble bath, a drop in the hormone oestrogen, causing dryness of the vulva, stress, lichen sclerosus or recurrent herpes simplex infection. Although genital warts don't cause pain, they can cause discomfort during sexual activity. So this also needs evaluation.