I've been there before. I got lucky enough to have a nerd as a roommate so I can talk with him about just anything and hold a conversation for hours without effort, and believe me that can be taxing in college with class in the morning. Probably the worst part is when warning your girlfriend that you're a nerd, and she disagrees saying I'm not and yet... whenever I talk about nerdy things, like Skyward Sword for instance, she gets irritated. lol So I understand completely where you're coming from. Just be yourself regardless of what people say or think, it's the easiest and best thing you can be.