8 week 6 days miscarriage??

I'm 8 weeks 6 days pregnant, and today I started bleeding around 9-9:30 this morning with painful, intermittent cramps. I didn't have any clots until 10:30ish tonight and I had a dark red, almost brown looking solid clot. (You know how you dissect animals in science? It was kinda liver shaped and feeling)

I'm really worried I'm miscarrying, but I've also heard you can bleed while in your first trimester.