still no AF but getting BFN

After having my 2nd Mirena removed 3 months ago (sept8) I've only had one cycle (oct29-nov4): I know it takes a while for your body to get back to normal but this is so frustrating! I can't really "plan" my cycle dates so I have NO clue when my fertile days are. I took ovulation tests since since about 6 days after my cycle and only got 1 positive. We have BD almost EVERY SINGLE day since my cycle ended. I've taken 2 pregnancy tests one on the 16th and one this morning but still BFN! Dr says everything is good (small cyst on left ovary) and nothing to worry about. I just hope things get back to normal soon and I'll get my BFP