Well, I don't know if "normal" and "weird" are useful terms to categorize what's happening here to begin with.
It's not uncommon to be scared of showing something deeply personal to others, usually because it makes us feel exposed and vulnerable. If the thought of showing this game to others does that to you, then maybe you put something deeply personal in the game somewhere. I suggest reflecting on this possible cause for a moment, and see if anything concrete comes to mind.
If so, you can try to reflect on what makes this game different and whether or not the fear that comes from this represents a real threat to you or not, and if so to which aspect.
Nothing really came to mind at first since it's a very mechanics heavy playtest without any of the narrative elements I was going to add it that I would expect to have more deeply personal elements, but when thinking about it more, you are probably right.
While I'm not really sure it's exposing anything threatening or vulnerable, it might be because the mechanics, more so than any other game I've made are very close to me in a weird, kinda personal way. It's the less dependent on pre-existing game conventions and ideas compared to any of my other games by a fair margin, which I guess makes it feel like if the whole idea falls apart it's representative of me and my ability to conceptualize ideas, rather than just my technical ability at actually putting the game together, which is something that feels more like a personal failing on my part and more reflective of me in general.
Reading that back I realize it sounds a little bit silly, and I don't think it's exactly what I'm feeling, but it's as good as I'm going to get, I've already spent like 15 minutes trying to word this already lol.
Anyway, thank you! I think knowing, at least in part why it makes me nervous helps me work with it a bit better? At the very least I feel less sick thinking about the idea now.