Weird discharge only during sex?

So my boyfriend and I were having sex a couple days ago and white foamy discharge with bubbles was on his dick and me. And the white color was legit the color of snow. It didn't have a smell. It has been happening the past few days and only during sex. My period was supposed to start today and I took a pregnancy test that showed Netflix so idk if I could be pregnant. (We're ttc so he does come in me. ) anyone else experience this?