any body ever experienced this.

OK my af started on the 19th ended on the 26 I had intercourse on Monday the 30 and July 4th I'm having light bleeding 2 hours later it stopped didn't even get on the panty liner what can this be and I was suppose to ovulate july 3. no bleeding on Saturday July 5 July 6th went to the bathroom noticed it was brownish pinkish blood the tiniest amount on the tissue that it wouldn't even get on a panty liner. What could this be? and no discharge today only cervical mucus