Breastfeeding questions.

Angelina • Daughter: Stella renee. August 6th 2012. Son: Azrael jack-michael January 30th 2016, Collen Nathaniel April 6th 2018

I'm son is 12 weeks now and I still haven't gotten a period. Has anyone else experienced this? When did yours return?

He sleeps through the night and so do I, is my supply going to drop? (He nurses CONSTANTLY during the day, like 24/7)

He's only 11lbs, Dr is concerned. How can I make my milk fattier so he gains weight?