
If you’re genuinely asking, it’s pretty much just if you were to grow boobs without hrt. It’s usually caused by a hormone imbalance in cis men. She may have noticed if your boobs have been growing, but in mentioning gynecomastia she also kinda offered you an excuse without outing yourself. Doesn’t mean she knows you’re trans. Having said that, if you’re trying not to come out to parents and they’re catching on you gotta be careful!
i have a friend who's buying it for me. if your family can't see your transactions you can try diy (note that diy is not cooking it up yourself like it sounds, it's buying it from an unofficial source thus bypassing medical institutions). i then just keep it in a place they're unlikely to look and only pull it out when doing doses.