Is it normal that im afraid to get close to my crush?

i like a manager very much at work and he likes me too, he always stares at me and tries to be around me and we always say hi to each other but most of the time im the one who starts .but whenever he tries to get closer to me i find myself backing off and i dont give him a chance. he is so cool and has so many friends while im not as cool as him and i dont have many as friends as him so im afraid if he gets to know me better he wont be interested anymore but i really really like him and im afraid he would give up on me and look for someone else. how do i stop the fear?