Weird Discharge while ovulating

I'm in my fertile window right now. My boyfriend and I just had sex doggy style (no protection) and when he pulled out I had creamy, white discharge on the sides of my vagina (not sure how to word it). Not sticky fertile mucus (I haven't produced that since being on BC two years ago). I think it's cum but my boyfriend says that's not how it's supposed to look. Idk what else it could be we're faithful to each other...