First Impressions? D8 The Parents!?

I'm meeting my boyfriend's parents tomorrow for the first time. Now, I'm a 17 year old senior who doesn't have a job or even my licence and he's a 15 year old sopre. We live in different cities and met through a friend. I'm gonna spend the day at his house tomorrow. He says I shouldn't worry but I can't help it D8 Any advice?