Advice please I’m so confussed? abit TMI

So according to glow today is supposed to be my OVU and when I went to the toilet I noticed blood when I wiped it was quite a lot I kept an eye on it all day and it’s just happened the once so far and a bit of spotting here and there but I am soo confused ? As this has never happened before! any one got any ideas of what it might be I’m not due on my period for another 15 days TIA :)