And now for some anxiety-dispelling efforts that are tailored specifically to my gender fears...
Affirmations for when HRT feels overwhelming and scary:
If you wish this could have happened to you accidentally—if, say, your body had produced this much testosterone of its own accord, perhaps instead of the estrogen-based puberty that you actually got—then it’s worth choosing and pursuing on purpose.
You could live the rest of your life disguising your dysphoric body with the most gender-affirming clothes possible—but why not make your body gender-affirming, too? You deserve it.
Billions of people are out there everyday, casually displaying their testosterone levels through their amount of body hair, the deepness of their voice, and so on. Why shouldn’t you join them? Why are your testosterone levels so exceptional that you feel the world might crash to a halt if you pursue this path?
You could look so good in swim trunks!
Imagine your niblings calling you Uncle Cam.
Most changes that occur on T can be countered, if you wind up hating them that much. For example, if you despise having hair in certain place, either shave it or save up for more permanent hair removal options. Detransition is a loaded subject for many reasons, but the fact remains that it is an option.
If you're worried that, as a nonbinary person, neither binary puberty sits quite right, then what does it matter if you "get it wrong" the second time around and don't end up completely satisfied? You weren't completely satisfied before, either. Odds are, this puberty will be better than the last. And if not, you will have a field day referencing the "two giant paint bubbles" scene from Spongebob.
Remember, you're on a very low dose right now. Your trans friends who are on high/full doses are still struggling to grow decent beards after multiple years on T, and they're probably looking at you terrified that you'll spontaneously develop a beard after three months of low dose T, like, "Oh, you sweet summer child."
In a similar vein, menopausal cis women are barely on less T than you. (Two pumps a week of the same dose, versus your three-on-the-cusp-of-four pumps.)
If you feel panic setting in, there's no need to quit HRT cold turkey. Take it one day at a time, and feel free to skip a day or two and lower your dosage if you're freaking out.
No matter what happens, you will always be there for yourself. You are doing the best you can and are only trying to follow your heart. That must count for something.