My boobs grew overnight!!!

So my bf n I went on a hike today n we took pics. I've noticed in all the pics my boobs look HUGE! I asked my bf n he said "yeah they do look bigger." Then when I went to go squeeze them I notice my left nipple was erect! I showed my bf n we are both at a loss, they are HUGE, feel heavy, VERY sensitive , one nipple erect (lol) n very sore. This is puzzling... I also just started back at the gym n have lost a few lbs but normally the first to go in fat are my boobs. I have been having 39-41 day cycles so I'm not due for my period til nov 12th so I don't think it's Pms. Help!! Plzzz???!