Back to back periods??

Hello i am 5 months PP and got my periods back in the 3rd month and that’s when my supply tanked unfortunately…. Anyways i have had periods after every 2 weeks and i am done! My doctor at that time prescribed me with a breastfeeding friendly birth control and said once i am not breastfeeding she can prescribe something more strong to regulate my hormones… my milk is dried up but im so guilty and still in delusions that i will try pumping again and it will come back… is this period thing related to this birth control? Or its normal and everyone is facing it too and with time it will get normal?