You don't self identify as a nationality though. You can self identify as French all you want but if the French Government disagree, then you are not actually French.
Whenshewas, I think what you are describing in your post is a mixture of wanting to express femininity and living in a female body.
I don't want to get to the stage where people feel they have to declare, 'well I breastfed but it meant nothing to me!' or 'the norm for my sex is to have a small waist compared to my hips but that is nothing to do with me' Of course people should experience the world within the body they have. We have sexed bodies.
Femininity is about personality traits, clothing etc and anyone can have those. But men don't have the shared experience of living as female bodied because they are in no way female bodied.
So I think lots of women go through pregnancy and experience ambivalence about it. But they are the only people who do. And it is only women who are supposed to have those particular relative waist and hip sizes. The healthy waist range for men is higher than that for women.
I don't think what you have written is a stereotype. It isn't a stereotype to compare yourself to the height, physical size and strength and pregnancy experience of other women. That is part of the feminist act of not seeing the male body and male experience as the human default experience.
What I don't see is what this has to do with gender identity. Gender identity is a different thing to you being aware that you have a female sexed body. If anything, it is the opposite. If you really believed in gender identity, then your explanation would be transphobic, wouldn't it? Because there is no physical difference between men and women, according to the theory of gender identity.
Shortcut, I think the image of the spectrum is useful (the Xyz one, not the one with numbers, which represents something different) because it potentially shows masculinity, femininity and non gendered experiences as being on different axes. So being more masculine does not make you less feminine. I think that is an improvement on putting masculinity and femininity on the same axis.
Whether any of these charts illustrates gender identity I don't know, because what is gender identity?