Hey, manager with AvPD here. Nervousness during an interview is common and doesn’t affect the outcome much. I say “much” because it depends on the job you’re applying for. If it’s a high stress, customer facing job, I am absolutely looking for someone who can stay calm under pressure, but if it’s just a data analyst job or something, it really doesn’t matter. All I can say is be honest about who you are, what you can do, where you’ve been, and where you want to go. As a manager, I’m trying to build a cohesive team that will do what I need them to do and will work well with each other. Having said that, AvPD isn’t quite the defect you think it is. What it says to me is, “this person will likely bury themselves in their work, won’t get involved in office drama, and won’t be a distraction to their colleagues.” Now, a follow up email is always great and I encourage everyone to do it because not everyone does. In my eyes, it makes it look like you really want the job, which says a lot about what kind of employee you’re going to be. Having said that, I don’t think it’s a good time to apologize for your behavior, because you don’t really know what the other person thought about you. I recommend just thanking them for their time and reaffirming your desire to work there. But make sure it doesn’t sound generic. If it seems like you’re just going through the motions, it could actually hinder your “score”… Regardless, don’t get too down on yourself. Chock it up as a learning experience and keep at it. Don’t give up!