I am 28 and developing breasts, been to doctors they can't find the cause, I am comfortable with self so I don't mind, it's my gf and such that I worry about when and if they get to be large enough to not mask. Now I am a small a cup.
As an avid gym rat I can vouch for anyone especially in this case about people in the gym....we look at everyone, especially in between sets. It's not an observation of any sort of anyone out of the norm such as "whoa he has breasts, is he transgendered?" It's more of a just looking around till ready for the next set, or observing others working out to see if they are doing anything we are not doing to try ourselves. 95% of the time people staring are not staring to be rude or judging, they are staring cause we have eyes, they are open so we look and look around. Your nipples are definitely quite feminine and honestly it's nothing to be ashamed of at all! Be proud of who YOU are not what YOUR body is. At first I went from surgeon to surgeon consulting surgeries, they told me give it 2 years before deciding cause tissue takes about 18-24 months to solidify otherwise it could be growing still and removal could be cause of regrowth. It's been 4 years and I've grown slow an steady and it keeps growing but i dont care anymore and eventually you probably wont either. It's an adjustment and it takes us off balance a bit cause obviously the growth is not wanted but it happens.
I doubt anyone thinks you are transitioning, if it looks like a duck sounds like a duck whatever else like a duck its a duck....if it looks like a guy talks like a guy and acts like a guy its probably a guy or a FTM not a MTF. As we get older our testosterone levels plummet a bit and breast growth is natural from it. Everything from xenoestrogens to phytoestrogens to other forms that create estrogens in our body can be the cause for earlier onset for Low T. If you are worried about it continuing may I suggest taking Zinc and Stinging Nettle. Zinc helps not just support and boost our immune systems greatly but is fantastic at creating a hormonal balance in our systems. As well as stinging nettle which is an herb that promotes testosterone by taking the Free T in our systems and putting it to work opposed to it sitting there doing nothing while estrogen continues to do its dirty work. I'd suggest an estrogen blocker too but honestly i'd talk to a supplement expert before doing so (NOT GNC A LEGIT SUP EXPERT) and see if its right for you cause it can cause adverse effects if not the right one or not cycled or whatever else that may be needed. But Zinc and Stinging Nettle do wonders.