I've been tracking my period for as long as I can remember. It always comes exactly when my app predicts it (maybe a day or two off every now and then). It was supposed to be here on Saturday. I had been experiencing normal pms symptoms. On Sunday I noticed a very small, light amount of blood. I have been experiencing symptoms of my period (cramps, mood changes, bloating), but I have not seen any blood. Is this just an irregular period?