What do you do when you barely get to see your boyfriend?

Well, it's not like I can call him 'cause he doesn't have his own phone, and I know his mom's number but he's with his grandparents through the week. I tried calling his grandparents but they always say he's not there when I know he is! Like yesterday, I called him to say good night and have sweet dreams and his grandparents said "he's not here hon, I'm sorry, good night." The thing is he was standing right there and he heard my voice and he knew I wanted to talk to him, I got emotional and started crying but he got pissed and stormed off and acidentally hit his grandmother and he's not the type of guy that'll hit a lady but his grandmother took it the other way around. He got in trouble and now he's on punishment so I have to wait another week to see him, that'll be two weeks, I can't take constantly not seeing my babbby. I love him to death and he feels the same way about me and this bullcrap is pissing us both off. No, I'm not going to break up with him so I advise you not to suggest that, please! Please, please, please, give me a lot of answers! This is making me really sad and depressed, so what do I do?