A couple of people have already told you how to salvage the situation. I'd like to give some advice on how to prevent such things in the future, not just with romantic relationships but human interaction in general. Obligatory "based on my experience" and YMMV.

When I was your age (c. 2004) I had recently/would soon come to a few key realizations. Most key, and last learned, was that by constantly overthinking how who might react to which potential situations to the point of in-the-moment paralysis wasn't just holding me back now, I was actively ruining my future. Yes, actively ruining by not acting. Secondly, the -vast- majority of people will have no recollection of the things that you consider so majorly embarrassing they keep you up at night. Finally, and this is more a corollary of the second point, the people that do remember those intactions are extremely focused on how they acted or failed to act. Just like you do.

I'm pushing 40, married my very extroverted best friend 15 years ago, and am still very much an introvert. I also tend to sleep peacefully at night. Well, not night, but that's because I worked third shift until my knees disintegrated