How Long Before you Get a BFP?

Ok long story short. Was on Mirena, got it removed, was on yaz, stopped cause it took away my period. Was on another BCP. Stop 2 weeks in to start ttc. never had period with mirena or yaz or the 2 weeks i was on the new BC. Stopped BC June 15th. severe cramping especially on one side about 2 weeks later. 29 days after stopping pills get what I think is period. was very light and lasted just 2 days. now Im extremly tired, bad heartburn at night, and by Tata's feel heavy. took numerous HPT and all neg. don't know when my period should be so dont know when to test. With first pregnancy i felt symptoms like 2 weeks before missed period. So my question is could what i thought was a period have been implantation bleeding? and could I have ovualted the week after I stopped BC?