How do you go about doing character analyses, and how confident were you in them starting out? I thought about starting to do my own to not only understand the stories I like better, but to also become a better writer myself. I'm really nervous to share my ideas with others, though, since they usually come off as stupid. For example, I see a few parallels, connections, and meaningful differences between Yosuke and Kanji's characters, but I'm afraid to try analyzing further.
Media analysis is absolutely imperative to develop as a skill, so even if you don't want to share it, it's great to talk to friends or even just write it out without posting. Practicing by stretching those writing muscles will help immensely with both ability and confidence. In your case, I think that you may just need to put yourself out there and not worry too much about how it may be received. Write for yourself.
I'm not sure I've ever thought about confidence as it relates to sharing my thoughts, I just do it, because I truly believe in what I believe and I want to share it with people and start a conversation that might fuel further exploration. And while there have definitely been times I've felt like an idiot for getting stuff wrong, (mostly misremembering phrasing or something that does alter the overall meaning where it no longer fits), you just kind of have to take the L and recalibrate. It doesn't mean all of your ideas are stupid, or that you yourself are, it's just that you put a few pieces together wrong or jumped to a conclusion before everything was considered. One of the most important things you can do when analyzing media is being open to different interpretations (not just from others, but also from yourself) until you sus out the one you can put your full weight behind. You might run through a couple different iterations before you land on one that ties everything together, and you might look back and scoff at how silly those previous thoughts were, or you might say, "hey, I was right!"
Don't underestimate the importance of the community aspect of fandom either. If you only see a few parallels, point them out (to a friend in private, or in your own post) somebody might be able to add on and give you a different perspective you didn't consider. It doesn't need to be complete when you're still in the process of exploring. Just try not to overreach, I'd actually say that while you should believe in what you're saying first and foremost, it's a good thing to not be completely confident, because it generally prevents you from making unfounded and ignorant claims; be receptive if you are under criticism, but you also don't have to accept anything and everything that a critic says.