Stopped BC! No AF

Stopped BC in June. Didn’t have a period in August. Was put on Provera for 5 days in September. Then my period came on September 20th. I took a ovulation test on the 4th came back positive for LH. Had sex on the 3rd, 5th, 6th and 7th. My ob told me on day 21 I didn’t ovulate. I was supposed to start my cycle on Thursday. AF is late. I took a test Thursday and it was negative. Still no period. Could it be possible my birth control is still in my system and that’s why I still don’t have my period or I got be pregnant????