PLEASE HELP ???!!!!

I was ovulating on the 15th when me and my boyfriend had unprotected sex. Today(the 21) I have this pinkish discharge. No funky smell, no pain , no itching..could this be implantation bleeding or something else? I'm nervous because my period is suppose to come the 27th and I'm in general curious If this could be implantation bleeding. Also the light pink looking discharge wasn't a lot and nothing was there when I wiped but it was on my underwear . thoughts? Please help!