Trans people please give advice!

So my boyfriend has spent years trying to figure out his gender orientation and in the last few months he's finally truly accepted that he's a guy and stopped trying to force himself to "feel" like a girl. Of course I'm super excited for him and we support each other endlessly in our genderqueer milestones.

He's been talking a lot lately about getting on testosterone and even having top surgery sometime in the next few years, so I went on Pink Cherry with him to pick out some briefs (that also work as a strap on ;P) and a packer to help with the disphoria, but now that they've come in the mail he seems really hesitant and uncomfortable about trying them on.

Did I possibly overstep a boundary or maybe push too far too soon? Or perhaps is he just nervous about it? He did pick them out himself.

I know this isn't really vagina or period talk, but I'm hoping maybe other trans people are on here and can give me their opinion on the matter.