sex scares me

I'm 17 and the thought of it sounds nice, although when it comes down to it I just can't. Idk what it is but I'm genuinely afraid to try sexual activity with someone but I want to. All I've ever done is kiss a few guys. And now at this point I feel so inexperienced compared to every single person I know. I'm not uncomfortable with my body although I would like to be more toned, so I don't think that's it. It took me a year after I got my period to be able to get a tampon in. This makes me feel so far behind, even less of a woman for not engaging. I hear my friends talk about it and in tv shows, movies, sex is everywhere. And it is so normal and natural. So since it is so normal and natural why am I afraid to try it? I'm going to get responses about doing it when I'm ready, but it's supposed to be natural, I'm supposed to be ready by now. Girls my age are already having babies I mean seriously what's wrong with me