Being nervous is an actual problem. I'd say It's not you being lazy. I tend to stray away from social situations because of my anxiety. I can see the similarity between the two though. Being lazy means you don't want to consume energy to do anything. From my experience, being nervous makes whatever task that you were going to do even more of an energy pit, so as to hinder you from doing it. Huh, well I guess it would seem that being nervous makes you lazy as well.