Big clots or tissue

Hello ladies, I have had maybe 3 periods this whole year. I was diagnosed with pcos last month as well as a bicornuate uterus. I was put on birth control and this week is the first “period” I’ve had since starting it. It has been really heavy all week but today I noticed some pretty big clots as well as something that looked like tissue and not just blood. Do you think it’s normal?