Very light pink spotting

So I went to the bathroom right before bed tonight and when I wiped I had very light pink on.the toilet paper. It is 4 days before my expected period (supposed to start the 30th) and my fiancé and Ihad sex 2 days before I was supposed to ovulate so it could be very possible that its implantation bleeding but i dont know. The last time this happened almoat the exact same way... sex a couple days before ovulation and then spotting very lightly I turned out to be pregnant. I'm just wondering other womens experiences with implantation bleeding and anything that may give me a little hope that I could possibly be pregnant again. Thank you in advance for any responses!