Thanks for the query.
It is difficult to tell the exact cause of your problem without examination and investigations.
After stopping the progesterone
pills, the withdrawal bleeding can come in around 4 to 5 days.
Before and during withdrawal bleeding, pain abdomen and backache etc symptoms can occur.
If you had unprotected intercourse
around the time of ovulation, there is possibility of pregnancy also. Endometriosis
can grow under the influence of hormones. And that can also present with pain abdomen.
So, you once consult gynecologist, get examined and go for blood test
If the test comes negative, the possibility of pregnancy is less.
Then you can go for ultrasound
to detect endometriosis.
If no abnormality is detected, symptomatic treatment may sufficient in your case.