Why do I feel shy to Ask my boyfriend for sex?

I just feel shy because I'm a girl. And I don't want him to think bad. But when I finally ask for it and give hints he doesn't take them or get them and doesn't initiate sex until I finally tell him I want sex. When he then starts I feel bad and I say no because I feel like I'm forcing him and like he only wants to have sex because I told him and he probably feels forced to please me. I never say no when he wants to have sex.