Im scared about going to school for the most ridiculous reasons?

so we have had a week off and i really dont want to go back. im really shy by the way. the girl i like me and her have been talking on facebook but i dont know if i will be able to talk to her in real ife because im so shy. in one of my classes im really uncomfortable because i sit around loads of pretty popular girls and they always start coversation with me. can someone help me overcome my shyness?