I woke up and my period had lots of small and big clumps in it, and its heavy flow.?

Tissue from uterus. Big clumps in your periods can signify blood that have accumulated into clots or blood mixed with tissue lining the uterus. As your lining in the uterus sheds, you will have bleeding. If you have excessive or prolonged bleeding (> 7 days), see your ob-gyn doctor for treatment options best suited for your needs.