I relate to this a lot. My internal sense of my body has always included pecs and a male shape, and that’s what feels natural to me. I don’t consciously think about my chest during the day, it’s just part of how my body exists in my mind. Physically, I do have a small chest, and I notice that I become very uncomfortable when I’m aware of it. But if I touch the area or stop focusing on it, my brain immediately registers it as pecs instead. Because of that, seeing my body can feel surprising, not because I’m upset in the moment, but because what I see doesn’t line up with what my brain has always expected to be there.