Just Recently I Notice Discomfort On My Right Labia Minora

Just recently I notice discomfort on my right labia minora ,I felt down there to find it felt like a bump was there I took a mirror to get a view then I seen a white patch (that's the best way I can describe ) it don't look like a wart etc but Im not really sure how to describe it..it hurts it especially when I urinate and the pea touches it ..it feels like when you have a open cut and you run water on it. Later on that day I checked it again and the white patch was gone the area looked just like the rest of my labia area but it still felt like an open wound. Today I check again and the white patch was there again. Lately I've been using black soap in that area along with rinsing with a shower head I have a history of allergic reactions down there ..I don't have any bad orders and smell fresher than usual there no itching or bleeding.. What could this be and do you have any suggestions for the pain??