First time mom question!

Hey everyone! This is a little long, but here is my story...
I am a first time mom to a sweet baby boy. He is 8 weeks old and I have been breastfeeding and also pumping at times. I have never had an issue with my supply. Two weeks ago, I started taking birth control. I began to notice that he would nurse and "empty me" faster but thought it may be due to him developing a stronger suck. I pumped the other night and realized my supply has gone way down. I immediately stopped taking the birth control and called a lactation nurse. The nurse told me to have a "nursing marathon" this weekend to try and build my supply back up. On top of this, I started my period for the first time pp the day after I stopped BC. I'm scared this will also make my supply go down or stop.

How long can you typically breastfeed after starting your period? Do you think my period will be regular or will it go away if my milk supply increases?

These crazy hormones are making me worry and stress about this :

Any help is greatly appreciated!!