Large Blood Clot?? (WARNING: GRAPHIC TMI PICTURE)

Help! I’m on my period and today I started exercising vigorously on a stationary bike. Halfway through my workout I started getting terrible cramps out of nowhere and rushed to the bathroom to take a hot shower. When I was done I peed and saw a large blood clot in the toilet. Is this normal? Am I overreacting? I usually get blood clots on my period but they’re much smaller. My cramps have also been much worse and much more frequent this week.

Any opinions/advice?

Thank you!