Yeah, I think that is one of the first absolutely undeniable, and very noticeable changes that we can clearly see with our eyes and feel. The HRT definitely affected my feelings right off the bat, but having actual physical changes happen like my boobs growing like this, is a very very welcome thing! It does make the whole thing way more real. But yikes do they hurt when my wife or daughter brushes up against them!
Oh, and just remember........Women come in many different shapes, sizes, and levels of attractiveness. Anytime you don't feel confident about yourself, just remember that. That you ARE without a doubt, a woman, and therefore are entitled to dress and present as one even if you feel like you might not look quite right. I struggle with this one myself. I still present as a rather femme dressing man because I allow my fear of what people will think of me, to keep me from wearing the skirts and dresses that I would love to wear. So I keep telling myself, "You are a woman....a kind of ugly woman....but there are plenty of ugly women out there, yet they are still women, and so are you." And it boosts my confidence up for a bit. Ha ha For now I am somewhat content wearing my tight skinny jeans and girls shirts and carrying my purse and things, but having been on HRT for over 3 months now, and having my boobs getting bigger, and me not even going to bother trying to hide them, I may find myself going "full-time" here soon.