Do you sometimes feel insecure about your knowledge of a certain fandom and how much you "belong" in it?

I've always had this nagging feeling in my mind for a long time now that I don't belong in any of the fandoms that I enjoy because of my lack of knowledge.

One of my fears is that I will cosplay as one of the characters, buy merch of them, or even use them as a discord PFP, and one of the members of the fandom will start quizzing me about it and I won't be able to answer them correctly.

On the surface, it sounds like an extremely small problem but this thinking of mine has persisted for a long time now and it's hindered me from enjoying the things that I love.

I was just wondering if anyone here has experienced something similar and how did you deal with this feeling?

I can guess it's probably something along the lines of imposter syndrome or something. But I genuinely don't know since I feel this fear is so "weird".