Pink-Brown "Mucus" after sex

We had sex at midnight this morning and afterwards I noticed the sperm that will leak shortly after was followed by a pinkish brown colored "mucus" any idea of why or what that could be?? I'm on the 10th day of my cycle and it hasn't continued since that and my app insights were saying that sometimes that occurs when an egg has been fertilized 6-14 days after ovulating and having sex which would put it at 1 & 2 days before having my first period after having my IUD removed and beginning TTC. I also had a very minute amount of this colored mucus yesterday randomly in the middle of the day and did not have sex on that day at all. Just looking for 2nd opinions no negativity please ☺.