Help!!!

So let me make this as clear as possible. I’m late on my period by 6 days and my last period was late anyways and it lasted for like 12 days which is really irregular for me. But anyways, recently i went to be put on birth control so obviously i’m not pregnant or they couldn’t have given me the birth control.. i have to wait till my period is over. i feel like i’ve been having pms symptoms but i keep overthinking everything. Why is my period taking so long to get here? Is there anyway i can make it come any faster?