What is going on

Usually on the first day of my period it’s pretty normal and I have a good amount of blood. Yesterday was one day late for AF, I had some spotting when I wiped and after wearing a tampon all day, it barely had anything on it- just a tiny bit of brown. I ended up taking out my tampon in the evening and didn’t need to put one in again. Today so far I have nothing. I’ve never experienced this before so just curious. Has anyone had similar experiences? We have been TTC for three years and this was my fourth round of Clomid.