Blood Clots and Periods!

KalPal • Me, Myself, & I
What does it feel like to pass a blood clot on your period?
I recently was sitting down and had an extremely sharp pain in my lower abdomin. I tried to stand up but could not move an inch without wanting to cry out in pain.
Is this normal? Could it just be a blood clot?
I started my period but not very much blood has been passing this morning.