Advice needed

Soo I’m in a mostly happy relationship. Going on two years. My bf is amazing for the most part. He provides for me emotionally when Im done, financially cause Im a broke college student (Im not smooching, I promise!) Our sex life is good with its occasional amazing days lol. Yet, sometimes I feel like he is so distant. He isn’t cheating. Or at least, I really don’t think so. Sometimes its like I talk to him about my days, my issues and he listens. But I never can get anything out of him. It feels a bit awkward to feel one sided in this sense... like I feel comfortable to tell him just about anything and, he’s so “shy”, I guess, with me. And between his phone and video games, I SOMETIMES just feel like Im thin air. I am emphasizing the sometimes because I want to recognize that we do have good moments too. And he isn’t a bad bf, that isn’t what Im trying to say. I just feel as if something is off in moments like the ones I mentioned above...

We’ve talked and he said that this is just him... he gets quiet sometimes. Yet, when we first met, I never saw this side of him. Am I overacting? Would this bother anyone else? What should I do?