Lip burn or possible cold sore?

So for some reason my corner of my lip has a light burning sensation but only when i pass my tongue on it … i have never had it before i dont see any blisters forming i dont have pain and it doesn’t burn when i eat citrus or anything…there is no marks in the area either and it started feel that way Sunday after i rub the side of my mouth with the back of my hand and today is Wednesday….im not sure if the perfume oil i had on irritated it or not . Any thoughts?