need an advice

Hey, I am looking for an advice from you girls. Back in November from last year my mom was at the hospital, I saw a guy that got my attention, I saw him a couple times while my mom was at the hospital. We finally got to talk but I was really shy. Now last week I was back at the hospital because of my grandfather. I saw him again and well I said hi! And he smile and look at his phone, the last time I saw him I was trying to get his attention but he said hi! And Lower his head look at his phone.  Do you guys have any advice how I can approach? I thinking maybe he is not interested.  I am a little curious. I don't see him that often? I wonder, you know.