Period came 4 days late. when i started i bled an enormous clot (never has happened before) could i have been pregnant and had a miscarriage ?

Menstrual cycles: It is common to skip or be delayed for a menstrual cycle . It is also more likely to happen if you are very athletic, gain or lose weight, using birth control pills, or have an eating disorder. Still, if you are sexually active, you could be pregnant. I would track your cycles to see if it happens often and see your doctor if you notice that it becomes more irregular.