TMI period question

Hi ladies, I've been PMSing and the app says I'm supposed to start my period tomorrow. While I was at work I thought it had started so I went to the bathroom and all I saw was (what seems like a lot) mucus and a teeny dot of blood in it. When I wiped there was a little more blood but it was very light colored and still mucus-y. I put a pad on anyway and there hasn't really been much all day.. I'm a week away from my "fertile window" and I haven't had sex in over a month or two so it's not implantation. I'm just confused as this has never happened to me before. Sometimes I will spot a little before my period comes full force but that's pretty rare but this is even less than spotting and I'm just confused why there is so much mucus.