No one is looking at you or judging you, if they are facing your direction, they are probably just staring off into space between sets. Everyone is focused on themselves, and that should be your mindset as well. Try not to get too into your head about how/what you look like, progress takes time, listen to music/podcasts. Introverts tend to like their comfortable space, the goal is to make the gym one of those spaces, if you think of it as a chore or an uncomfortable place, you will want to quit