11 dpo with 3 days left until AF is supposed to arrive. I’ve had frequent urination for a couple of day’s as well as very mild cramping occasionally. I’ve had a couple of small brown spots when wiping today and usually don’t spot until the day I actually start my period. Is it possible this could just now be implantation happening?

(Had unprotected sex many times from the end of my last period up until predicted day of ovulation and maybe a day or two after it)