Hard clots

I started my period about 5 days ago. It started with very bad cramps and normal amount of bleeding. This evening I noticed that there was a clot that was super hard and looked like the string of a tampon, it was about an inch long. I don’t use tampons so I know it was not from that. I used the bathroom about 30 mins later and there was were 2 light pink/ almost tan colored clots the size of B.B.’s. I was just wondering if anyone has any suggestions on what could have caused this. I tried google and found nothing.