HELP! New mum meltdown 💔😭

So my daughter is 14 weeks old and yesterday she did a poo and was being changed when my mum realised she doesn't have a vaginal opening. I have never realised this before as this is my first child so it never registered to me how a baby genitals is supposed to look💔😭. I immediately called the doctors to discuss my fear and they told me not to worry because things like this happen. They have booked us in for an appointment asap. The doctor said this should of been spotted on her newborn check and her 6 week check but I never actually saw them examine her vagina. I am so anxious about what this means or how this actually happened. Has anyone gone through this or know of anyone thats gone through this and has any advice?