Pregnant or light period??

So I use to have crazy irregular periods but ive been on birth control for over a year now and since then my periods have been exact and very light. My period was due yesterday. I had very light cramps and mood swings, as usual. But instead of bleeding I just had a little light brown spotting. And the same spotting the day before my period should have started. I did ovulate about a week ago, I had the thick white discharge for a little bit so that would be my ovulation right? So would the brown spotting be my period or am I late?