My Period Was 3 Days Late, Then Started With Clots

My Period was 3 days late, then started with clots and a heavy flow. I'm suspected of having endometriosis but my cycle has never started that late. And then during, I passed a fleshy looking clots about the size of a toonie. And than continued passing clots, even why my flow was light (this isn't normal for me) on the last day of my period, where the excess/old menstrual flow is coming out, I past a tubish looking clot. What might this be? I've been trying to conceive and had symptoms of pregnancy... If I was pregnant, could I still be?