My boyfriend won't communicate with me?

Me and my boyfriend have horrible communication. I'm 19, he's 21. We've been together for 2 years. We don't live together yet, but we were talking about it. We never talk unless it's in person! Idk if I'm just being needy but he ignores me 12+ hours a day. I send him a text when I wake up and call. He doesn't answer. I send him another text around 2 and he doesn't answer. I'll give him a call around 9 when I go to bed, and he doesn't answer. It's hard for me because when we spend time together we have such a good time, we spend whole days together and it's amazing. But it's so hard to get a text back from him or even answer a call. I used to be one of those girlfriends that was always texting him like every hour, but since he never responded I only text him 3 times a day. We both go to the same university, and currently I don't work because I'm full time. he does have a job but I'm pretty sure he doesn't work 7am-midnight with no breaks at all. When he does call me it's at like midnight or later, when I'm asleep. Is there a way to adress this? When I try and tell him all he says is "oh you'll be fine." Or "oh it's okay don't worry about it." But it sucks because sometimes we won't talk for 3 days straight. Is this just me?