Light pink streak on underwear after maturation

Is it possible to have light pink discharge only saw it once and post maturation without penetration. When I wipe nothing there. It was very small (like 1 inch streak) and light and only noticed it on the underwear. I’ve never had this before post orgasm so kind of freaked out but embarrassed to call doctor. 24 and a half weeks now and saw doc yesterday who said everything looked good but this happened today.