What is my period doing?!

I've been off the pill since November to ttc. My period has always been regular. So last week I got a few period pains and on Thursday or Friday I started having brown discharge which is normal for me at the start of my period which was fine as this app said I was due on this week. Usually by Saturday and Sunday I'm fully flowing and cramping like mad. This month is a bit different as had light spotting (enough to need to wear a pad but not change often) but yesterday I only had spotting when I wiped myself when using the bathroom. Today I woke up and my pad is completely clean from overnight which is unusually for me. I feel period pain twinges but nothing to the extent of it usually is. My boobs are sore and I feel tired but that's also normal for me.