Ive been on depo for 3 years. No other birth control ever worked. And in 3 years I haven't had a period. No cramping or bleeding in any way. But I have been bleeding for 2 weeks now. And I am not due for my shot. Also had biopsy done on my uterus as is very swollen., since my baby sister died from stomach cancer. So is this start, stop period normal? It seems to be in 6 to 8 hour cycles.