Hi!
If you were my patient, I would ask you to come in for an ultrasound of the uterus. I would want to rule out any retained tissue within the uterus. I have seen tiny pieces of placenta or membrane cause major problems.
I would also run some tests to rule out infection as endometritis can also cause bleeding.
If nothing was found, I would recommend continuing birth control or other hormonal therapy for awhile -- not indefinitely.
Congratulations and Good Luck!
Dr B
Is the bleeding caused by endrometritis something that can be stopped with hormonal therapy or birth control?