Possible IB! Can anyone help?

So AF is due today, but because I have PCOS, it not showing up today didn't really throw me off. At around 4am, I went to the bathroom and noticed a very, very (I mean VERY) small amount of blood and just figured AF was coming as predicted. I popped in a tampon in case it came while I was sleeping, but haven't had anymore bleeding since. I've never really had any kind of spotting before AF before and after numerous google searches, I've realized it could've been IB. Can anyone give some insight please???