Boobs are bigger?

So, my breasts look & almost feel bigger/heavier than normal. I JUST upgraded from 38D to 40D like 2 weeks ago & my new bras were a little roomy but now they’re almost completely filled out. Each breast used to be one handful big, but they’re now nearly 2 handfuls?! (Not to be weird.)

My period is 2 weeks late as of tomorrow, I’ve been eating a crap ton more, and had severe stomach pain yesterday. (Like, really bad knives stabbing me repeatedly, then fading, then coming back again over & over)...

I’m 16 and a virgin, so there’s no way I’m pregnant. Any ideas what’s going on??