Pink spotting after sex

So ive seen a lot of pics of supposed implantation bleeding lately and today after sex, my fiance had pointed out that i was bleeding a little. So i got up and wiped and it was a very light pink, but obviously there. I didnt notice any pain during sex. I have had sex (unprotected) just about every day this month, including on the predicted ovulation days. Im a little over a week away from my period. So what i want to know is, is this something that any of you have experienced after sex? Or should i be buying a pregnancy test here in a few days?