Possible Pregnancy after Surgery

Patient: I had a surgery to remove my appendix. I started bleeding as though I was on my period the day after the surgery. I was one the depo shot. Could the shot have worn off from surgery? And could I be pregnant after having intercourse days after the surgery, while still bleeding some? The bleeding has ended a week after the fact.

Symptoms: Light headed, nausea, need of vomiting (haven’t don so)