From what it sounds like you are actually describing ovulation. When you get thick stretchy discharge that usually means a womans ovulating! So I would BD asap! And even so if you had sex three days ago then that sperm could still get you pregnant cuz sperm can live up there for 3-5days! Good luck
No, it's probably a sign that you are about to ovulate. Look up "cervical mucus" or "eggwhite cervical mucus."