Help! 😔

so the last week my boobs have been pretty sore off and on... (how I knew I was pregnant with my daughter) but I never get sore boobs during my period and my heart rate has felt elevated... So I was really hopeful for a BFP this weekend.. AF is due Sunday. Tonight at dinner I went to the bathroom and was bleeding really heavy with a bunch of blood clots (which I also never get during my regular cycle). I miscarried in Feb, and it reminds me of the way my first miscarriage started... Is it possible I'm miscarrying already  or just having an unusual period?