I bled on tuesday last week and tuesday this week and my period not due until the 7th. no cramps, just moderate bleeding with clots. what can this be?

A hormonal imbalance: ..is usually the culprit when there is bleeding or spotting between periods. If you're on a hormonal contraceptive, this may need to be changed. If not, you should see your doctor about it. Reproductive hormone levels & thyroid function should be checked. If the bleeding is heavy, a blood count & iron status should also be checked. Hope this helps. Dr. Anne.